92 Ls400 Vibration

[pishta]

I get a vibration when I drive my Lexus. Its not a clunking suspension type vibration, but one like the tires are overinflated (like Im driving on wooden wheels) or it might be a transmission vibration (bad trans mount?) Or a bad wheel bearing? Im not really up on these cars suspension but I did change the lower ball joints and checked anything I could while I was down there. The UCA's are a tiny bit worn, but it moves just a hair when I pull on it. What should I look for? All the bushings I could see were good and the car has only 92K on it. It irks me to know that my 96 Plymouth Breeze rides better than this car! No clunks over bumps, just an almost grinding vibration while driving, more noticeable when driving slow. I can feel it in the steering wheel as well as the floorboard. Thanks

[flogdpup]

I get a vibration when I drive my Lexus. Its not a clunking suspension type vibration, but one like the tires are overinflated (like Im driving on wooden wheels) or it might be a transmission vibration (bad trans mount?) Or a bad wheel bearing? Im not really up on these cars suspension but I did change the lower ball joints and checked anything I could while I was down there. The UCA's are a tiny bit worn, but it moves just a hair when I pull on it. What should I look for? All the bushings I could see were good and the car has only 92K on it. It irks me to know that my 96 Plymouth Breeze rides better than this car! No clunks over bumps, just an almost grinding vibration while driving, more noticeable when driving slow. I can feel it in the steering wheel as well as the floorboard. Thanks

Here's the Lexus repair manual's troubleshooting guide for the suspension. I hope it helps you isolate the problem. I've replaced so many suspension and steering parts on mine that I know how you feel.:cries: Unfortunately it was before I felt confident/comfortable working on my Lexus and so I wasted a lot of money paying someone to do what I could have done all along. Good luck with yours.

sa_4_suspension_and_axle_troubleshoot.pdf

[landar]

Pishta....it is very difficult (impossible, actually) to identify your problem w/o actually hearing, seeing, feeling,

your car's symptoms. And I know how frustrating vibrations can be. They are only topped by strange noises.

That said, I would advise you to look not for a some complicated, obscure issue, but

rather for the simple things. You said it was almost like the tires were overinflated. I would check the tires first.

Try rotating front->back and see what happens (doesnt cost anything but some time). Also, when the vibration is

occuring, try throwing her in neutral to rule out transmission issues. In other words, keep experimenting and look for

something rather simple. My bet is on a tire(or tires) or possibly a wheel bearing. Many a time, a belt within the tire will break

or become distorted and cause problems.

If you get to your wits end, seek professional counseling! ie: a good tire/alignment shop. Many times the diagnostics is free

or very reasonable.,

In any case, let us know what you find when you finally get her fixed so we can throw a virtual party

[pishta]

I get a vibration when I drive my Lexus. Its not a clunking suspension type vibration, but one like the tires are overinflated (like Im driving on wooden wheels) or it might be a transmission vibration (bad trans mount?) Or a bad wheel bearing? Im not really up on these cars suspension but I did change the lower ball joints and checked anything I could while I was down there. The UCA's are a tiny bit worn, but it moves just a hair when I pull on it. What should I look for? All the bushings I could see were good and the car has only 92K on it. It irks me to know that my 96 Plymouth Breeze rides better than this car! No clunks over bumps, just an almost grinding vibration while driving, more noticeable when driving slow. I can feel it in the steering wheel as well as the floorboard. Thanks

Here's the Lexus repair manual's troubleshooting guide for the suspension. I hope it helps you isolate the problem. I've replaced so many suspension and steering parts on mine that I know how you feel.:cries: Unfortunately it was before I felt confident/comfortable working on my Lexus and so I wasted a lot of money paying someone to do what I could have done all along. Good luck with yours.

sa_4_suspension_and_axle_troubleshoot.pdf

Thanks. I will look into the trans/motor mount, as it feels like a rotating vibration and I feel it in the controls. Im also wondering about the steering damper or whatever that shock absorber looking thing is under the rack. When I hit a small bump in a turn the wheel kinda jumps. Tie rod ends? Im a DIY'er to the fullest extent, but will swallow my pride and have a indie Lex mechanic look into this along with analignment. He did wonders to my Dads SC400. Oh yeah, My correct spec Kelly tires say 44psi, but the door says 36psi(OEM gumball tires?) who do I go by?

[IansLexus]

Thanks. I will look into the trans/motor mount, as it feels like a rotating vibration and I feel it in the controls. Im also wondering about the steering damper or whatever that shock absorber looking thing is under the rack. When I hit a small bump in a turn the wheel kinda jumps. Tie rod ends? Im a DIY'er to the fullest extent, but will swallow my pride and have a indie Lex mechanic look into this along with analignment. He did wonders to my Dads SC400. Oh yeah, My correct spec Kelly tires say 44psi, but the door says 36psi(OEM gumball tires?) who do I go by?

Go off whatever the tire says.

Hmm... weird problem. Well I'm gonna throw a couple ideas out there for ya. They might not be correct, but you can find that out, because you actually know what it feels lile.

1. First of all, tires can get damaged internatally. This can cause symptoms similiar to failed/bad suspension parts.

2. Obviously check your joints, make sure they are binding or damaged.

3. Does it seem like a loose, bent or outofbalance axle or driveshaft?

A bad wheel bearing can usually be found be a throuough test drive. Bearing noises are found by noting if the sound happens when turning R/L or driving straight. The weight shifts onto the L side when turning hard R, and viceaversa. They get worse as speed increases, too.

But definitely let us know what you find!! I'm curious!

cheers mate

[elvis]

I get a vibration when I drive my Lexus. Its not a clunking suspension type vibration, but one like the tires are overinflated (like Im driving on wooden wheels) or it might be a transmission vibration (bad trans mount?) Or a bad wheel bearing? Im not really up on these cars suspension but I did change the lower ball joints and checked anything I could while I was down there. The UCA's are a tiny bit worn, but it moves just a hair when I pull on it. What should I look for? All the bushings I could see were good and the car has only 92K on it. It irks me to know that my 96 Plymouth Breeze rides better than this car! No clunks over bumps, just an almost grinding vibration while driving, more noticeable when driving slow. I can feel it in the steering wheel as well as the floorboard. Thanks

Pishta,

Your problem sounds exactly like mine for my 1991 Lexus LS400 with 170K miles on it. Its like you are going over a washboard or have wooden wheels. I can tell you for my car it wasn't: tires (tried three sets, two sets of them new and ok on the other cars); tie rod ends, replaced inner and outer on both sides, lower control arm bushings (replaced both sides), or tire pressure, rotors, brake pads and brake calipers - all changed. I also pulled the drive shaft and checked the center bearing and differential. Smooth as glass. The steering rack is tight and its bushings. The car is very good now in all respects except the vibration. I feel it mostly in the steering wheel at 35-40 mph. All the above changes had no effect on the vibration.

Not much left for me except wheel bearings. Note that I still get the vibration with the engine shut off and coasting in neutral. Occasionally, for the first 1/2 mile, when the car is cold, I don't get it. The rest of the time its there. It built up slowly over 1-2 years.

Please let us know if you make any headway on it.

[Bali26]

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

[90LS400Lexus]

My old 90 LS400 had a very annoying vibration between 35-45 mph. I had it everywhere. I finally took it to the Lexus dealer and they ran some tests. Come to find out, the tires were "cupped" due to poor alignment (shop did not do an alignment after new rear struts were installed).

[elvis]

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

[elvis]

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

Hi This is Elvis,

I didn't find any noise, rumble etc. in the front wheel bearings either under load or not under load that may be causing the steering wheel vibration. I went on and pulled the driveshaft. The U-Joint in the center of the driveshaft had the tell-tale red dust around it indicating the needle bearings got dry of grease and ate themselves up. Center bearing feels ok, but I may go ahead and change it.

The vibration was faint about two years ago. It has become very pronounced. Its started at 35-40 mph but broadening out now to 30-60. Its about 25 HZ which is the right frequency for drive shaft revolutions at 38 MPH. I'll let you know. BTW, the new Michelin Primacy tires and suspension parts really restored the steering to what a Lexus should be. What a pleasure to drive. The Akebono ceramic brakes are great also.

The trans and engine mounts looked good and passed the torque test but its hard to tell. They didn't move much.

[UCF3]

When was the last time you had your tires balanced? Also are they new tires?

Not sure if you've already done these.

You could stop by a cheap shop like a Walmart and ask them to balance your all four wheels and tires. You may want to look for a bent wheel or a bad tire(belts have moved). the balance machine and the shop will eliminate that.

Next if you had any major suspension work done, like what 90LexusLS400 was experiencing, changed control arms, added a cross bar in the past; you may need to have an alignment done.

start with these.. and work your way to the more detail oriented stuff.

[elvis]

When was the last time you had your tires balanced? Also are they new tires?

Not sure if you've already done these.

You could stop by a cheap shop like a Walmart and ask them to balance your all four wheels and tires. You may want to look for a bent wheel or a bad tire(belts have moved). the balance machine and the shop will eliminate that.

Next if you had any major suspension work done, like what 90LexusLS400 was experiencing, changed control arms, added a cross bar in the past; you may need to have an alignment done.

start with these.. and work your way to the more detail oriented stuff.

Thanks for the reply. All were good suggestions.

Some of the data about past fixes were on earlier posts. A summary is that I started with tires. Tried two known good sets from other cars, tried rotation and a couple of balances. I ended up putting the new Michelins on anyway since I needed tires. I knew I had a tougher problem since all the tire swaps over the past six weeks had no effect on the vibration at 38 mph at all. It is very smooth over 60 mph. I did have worn lower ball joints earlier and had replaced those not too long ago. They were significantly worn due to a design defect in the earlier ears, I think 90 and 91. I decided to tighten up the whole steering and suspension due to "wandering" and a lose feel in the handling. It also had a shudder when I came to a stop (one warped rotor in back). I got going and replaced the upper ball joints (not too bad though but expensive), lower control arm bushings (very bad), inner and outer tie rod ends (medium play) and rear trailing arm bushings (very, very bad, almost no rubber left that was doing any good). I have to say that the handling feels like a new car now and its a real pleasure to drive. I would recommend this to any serious do-it-yourselfer if you have the skills or a good friend you can learn from. It is a lot of work. I used after-market parts, and some from EBay (all new parts though) to save expense except the lower control arm bushings which were actually cheaper at the Lexus dealership. When it was complete, I took it in to a known, good alignment shop. It was satisfying doing the work but note that I also have a friend with a 20-ton press which helped a lot. Even with that, there were tough spots. By the time its over, I'll probably have gone through the whole car. Next is gauges and the LCD display.

If anyone has changed the drive-shaft U-Joint and has had some effect, please let me know.

Thanks

Elvis

[nc211]

http://us.lexusownersclub.com/forums/index...=WOBBLE&st=

Read the 1st post, then proceed to the last two pages, othrwise you'll be reading for a bit. At the end of the day, my driveshaft U joints were binding up. The new shaft made a very noticable difference.....smooth as silk!

[lexusnutt]

I get a vibration when I drive my Lexus. Its not a clunking suspension type vibration, but one like the tires are overinflated (like Im driving on wooden wheels) or it might be a transmission vibration (bad trans mount?) Or a bad wheel bearing? Im not really up on these cars suspension but I did change the lower ball joints and checked anything I could while I was down there. The UCA's are a tiny bit worn, but it moves just a hair when I pull on it. What should I look for? All the bushings I could see were good and the car has only 92K on it. It irks me to know that my 96 Plymouth Breeze rides better than this car! No clunks over bumps, just an almost grinding vibration while driving, more noticeable when driving slow. I can feel it in the steering wheel as well as the floorboard. Thanks

Here's the Lexus repair manual's troubleshooting guide for the suspension. I hope it helps you isolate the problem. I've replaced so many suspension and steering parts on mine that I know how you feel.:cries: Unfortunately it was before I felt confident/comfortable working on my Lexus and so I wasted a lot of money paying someone to do what I could have done all along. Good luck with yours.

sa_4_suspension_and_axle_troubleshoot.pdf

Thanks. I will look into the trans/motor mount, as it feels like a rotating vibration and I feel it in the controls. Im also wondering about the steering damper or whatever that shock absorber looking thing is under the rack. When I hit a small bump in a turn the wheel kinda jumps. Tie rod ends? Im a DIY'er to the fullest extent, but will swallow my pride and have a indie Lex mechanic look into this along with analignment. He did wonders to my Dads SC400. Oh yeah, My correct spec Kelly tires say 44psi, but the door says 36psi(OEM gumball tires?) who do I go by?

Strut Rods will take care of the jumping problem. Even a warped or worn brake rotor will create vibration. Tires are EXTREMELY important. Get the car "road force" balanced. It will spot out of round conditions. LS's are very sensitive. I did everything above and eventually got rid of it. Good luck.

[lexusnutt]

Oh yeah, forgot about this one. Retorque the driveshaft

[elvis]

http://us.lexusownersclub.com/forums/index...=WOBBLE&st=

Read the 1st post, then proceed to the last two pages, othrwise you'll be reading for a bit. At the end of the day, my driveshaft U joints were binding up. The new shaft made a very noticable difference.....smooth as silk!

Thanks! I read the whole story. WOW! You stuck with it and found the problem and the post helped a lot of people. Sounds like you got good prices too. The Lexus can be so smooth but there are a lot of potential causes of vibration. I'll let the forum know on mine. I used to be into early Corvette's and had to change U-Joimts quite often. I should have thought of that earlier. Mine has the red, rusty powder around it like the bearings have ground up after it went dry. So, I am hopeful. May be awhile before I can get to it.

Elvis

[elvis]

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

I pulled the drive shaft out today as well as the transmission mount. The driveshaft has a single u-joint in the middle near the center bearing. Mine is definitely bad. Should have caught it the first time. You can feel that it is grooved when its moved. Its very rough. Feels and sounds exactly like what I feel in the steering wheel and gas pedal. I have high hopes. I'll know in a few days. The u-joint is staked. No one lists a part number for it since they consider it not serviceable. Easy to get around though. Its a common u-joint. I’ll replace it with one that has the in-board cir-clips rather than staking a new one. The trans mount looks like its seen better days. Its not broken but the rubber is soft and flattened Will change it and the driveshaft center bearing.

Elvis

[mwc0610]

Elvis, Can you tell me how you got around replacing the driveshaft and found another universal joint that would work in your lexus. I have a 95 Lexus ls400 with the same exact problem. I've been told everything except the driveshaft by other mechanics and they were all wrong. I can't afford to buy a $500 driveshaft but want to make sure I get the right universal joint to put on. Also you talk about changing the Driveshaft center bearing. I don't know a lot about driveshafts and would be very interested in where you found your parts to do instead of replacing the entire driveshaft.

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

I pulled the drive shaft out today as well as the transmission mount. The driveshaft has a single u-joint in the middle near the center bearing. Mine is definitely bad. Should have caught it the first time. You can feel that it is grooved when its moved. Its very rough. Feels and sounds exactly like what I feel in the steering wheel and gas pedal. I have high hopes. I'll know in a few days. The u-joint is staked. No one lists a part number for it since they consider it not serviceable. Easy to get around though. Its a common u-joint. I’ll replace it with one that has the in-board cir-clips rather than staking a new one. The trans mount looks like its seen better days. Its not broken but the rubber is soft and flattened Will change it and the driveshaft center bearing.

Elvis

[pishta]

Elvis, Can you tell me how you got around replacing the driveshaft and found another universal joint that would work in your lexus. I have a 95 Lexus ls400 with the same exact problem. I've been told everything except the driveshaft by other mechanics and they were all wrong. I can't afford to buy a $500 driveshaft but want to make sure I get the right universal joint to put on. Also you talk about changing the Driveshaft center bearing. I don't know a lot about driveshafts and would be very interested in where you found your parts to do instead of replacing the entire driveshaft.

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

I pulled the drive shaft out today as well as the transmission mount. The driveshaft has a single u-joint in the middle near the center bearing. Mine is definitely bad. Should have caught it the first time. You can feel that it is grooved when its moved. Its very rough. Feels and sounds exactly like what I feel in the steering wheel and gas pedal. I have high hopes. I'll know in a few days. The u-joint is staked. No one lists a part number for it since they consider it not serviceable. Easy to get around though. Its a common u-joint. I’ll replace it with one that has the in-board cir-clips rather than staking a new one. The trans mount looks like its seen better days. Its not broken but the rubber is soft and flattened Will change it and the driveshaft center bearing.

Elvis

Well, I started this thread so Ill add again to it. I replaced my rear carrier bushings and that helped about 90% meaning it has reduced the vibe to about 10% of what it was. My shafts were twistable with my hand so I found a set of bushings on craigslist for 40 bucks, too good to pass so I did them and WOW, what a difference. My bushings didnt look bad, they were just soft. It is hard to see in there because the location of the bushings, but I got then out, put the new ones in and drove around. No more rear end wandering and the vibration from the rear seems to be gone. Im going to look into the driveshaft U-joint. ANy cross reference for a part number?

[elvis]

Elvis, Can you tell me how you got around replacing the driveshaft and found another universal joint that would work in your lexus. I have a 95 Lexus ls400 with the same exact problem. I've been told everything except the driveshaft by other mechanics and they were all wrong. I can't afford to buy a $500 driveshaft but want to make sure I get the right universal joint to put on. Also you talk about changing the Driveshaft center bearing. I don't know a lot about driveshafts and would be very interested in where you found your parts to do instead of replacing the entire driveshaft.

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

I pulled the drive shaft out today as well as the transmission mount. The driveshaft has a single u-joint in the middle near the center bearing. Mine is definitely bad. Should have caught it the first time. You can feel that it is grooved when its moved. Its very rough. Feels and sounds exactly like what I feel in the steering wheel and gas pedal. I have high hopes. I'll know in a few days. The u-joint is staked. No one lists a part number for it since they consider it not serviceable. Easy to get around though. Its a common u-joint. I’ll replace it with one that has the in-board cir-clips rather than staking a new one. The trans mount looks like its seen better days. Its not broken but the rubber is soft and flattened Will change it and the driveshaft center bearing.

Elvis

Well, I started this thread so Ill add again to it. I replaced my rear carrier bushings and that helped about 90% meaning it has reduced the vibe to about 10% of what it was. My shafts were twistable with my hand so I found a set of bushings on craigslist for 40 bucks, too good to pass so I did them and WOW, what a difference. My bushings didnt look bad, they were just soft. It is hard to see in there because the location of the bushings, but I got then out, put the new ones in and drove around. No more rear end wandering and the vibration from the rear seems to be gone. Im going to look into the driveshaft U-joint. ANy cross reference for a part number?

Taking it into a supplier Monday or Tuesday to match it up and get one with the retaining clips on the inside. I'll post a number for it. Note that I didn't notice any trouble with the U joint by turning the drive shaft while in the car. It felt smooth then. (It didn't feel smooth when I had the car running on jackstands at 38mph Anyone reading this, be very careful of this procedure). When I had it on the bench and the two sections of the drive shaft disconnected, then the groove and roughness could be felt when I moved it in either axis. It has 173K miles on it. Probably started going bad at about 150K.

Elvis

[elvis]

Elvis, Can you tell me how you got around replacing the driveshaft and found another universal joint that would work in your lexus. I have a 95 Lexus ls400 with the same exact problem. I've been told everything except the driveshaft by other mechanics and they were all wrong. I can't afford to buy a $500 driveshaft but want to make sure I get the right universal joint to put on. Also you talk about changing the Driveshaft center bearing. I don't know a lot about driveshafts and would be very interested in where you found your parts to do instead of replacing the entire driveshaft.

Hi Pishta,

My 91 LS400 end with 170K miles (hi Elvis) has the same problem. I can feel vib from steering as well as footwell but only under load when accelerating. Yesterday i replaced trans mount. It removed the D versus N vibration. I also installed arnott UCAs (so cheap and good)

But the steering and footwell vibration still the same. Now im looking to replace engine mounts next but after putting front wheels in rear to rule them out first. Also PS rack bushes could be bad...

If you need to buy trans mount buy from autopartsplace.com cos they have free shipping on over 50 buck purchase. I bought mount, oil filter and oil drain gasket to make it a 51 dollar order :)

Keep us posted cheers

I pulled the drive shaft out today as well as the transmission mount. The driveshaft has a single u-joint in the middle near the center bearing. Mine is definitely bad. Should have caught it the first time. You can feel that it is grooved when its moved. Its very rough. Feels and sounds exactly like what I feel in the steering wheel and gas pedal. I have high hopes. I'll know in a few days. The u-joint is staked. No one lists a part number for it since they consider it not serviceable. Easy to get around though. Its a common u-joint. I’ll replace it with one that has the in-board cir-clips rather than staking a new one. The trans mount looks like its seen better days. Its not broken but the rubber is soft and flattened Will change it and the driveshaft center bearing.

Elvis

Well, I started this thread so Ill add again to it. I replaced my rear carrier bushings and that helped about 90% meaning it has reduced the vibe to about 10% of what it was. My shafts were twistable with my hand so I found a set of bushings on craigslist for 40 bucks, too good to pass so I did them and WOW, what a difference. My bushings didnt look bad, they were just soft. It is hard to see in there because the location of the bushings, but I got then out, put the new ones in and drove around. No more rear end wandering and the vibration from the rear seems to be gone. Im going to look into the driveshaft U-joint. ANy cross reference for a part number?

Taking it into a supplier Monday or Tuesday to match it up and get one with the retaining clips on the inside. I'll post a number for it. Note that I didn't notice any trouble with the U joint by turning the drive shaft while in the car. It felt smooth then. (It didn't feel smooth when I had the car running on jackstands at 38mph Anyone reading this, be very careful of this procedure). When I had it on the bench and the two sections of the drive shaft disconnected, then the groove and roughness could be felt when I moved it in either axis. It has 173K miles on it. Probably started going bad at about 150K.

Elvis

Update: (and to mwc0610)

Looks like I do not have the solution I thought I had. I removed the U-Joint with a "C-Press Ball Joint Tool" from Harbor freight. What a tool! On sale now for $29, without shipping. Its a copy of the Matco Press. Had no trouble getting the U Joint out. It is very bad, very rough and grooved.

The bad news is that I cannot find a replacement. I downloaded catalogs from major U-Joint suppliers like Neapco, Rockford and GMB. No one lists the size required. I did find that it is a very special U-Joint as is the entire drive shaft. Its a design similar to the Mercedes, circa 1990. The Mercedes U-Joint came the closest. Right length, wrong cap diameter. Unless I have a breakthrough tonight in finding one, I'll order a rebuilt driveshaft.

(to mwc0610)

I wish I could find a correct U-Joint to install. Lexus is great but I can't understand why they didn't make this driveshaft more serviceable. At least the new driveshaft will have a new center bearing and be balanced. The center bearing is available on-line at Parts.com for the 1990 thru 1994. I am not familiar with the 1995 LS400 but I assume it has a center bearing too. I didn't see a 1995 listed at Parts.com. Its a little rare but you can probably find it. So many things can cause vibration its hard to pin down, especially if its a driveshaft. My car fooled some real experts that I ddeal with all the time. I couldn't be sure until I had mine apart. But as others have said, try the simpler and cheaper things first. Looks like you did that already though.

For the forum: Any recommendation on a good drive shaft supplier?

Elvis

[pishta]

The bad news is that I cannot find a replacement. I downloaded catalogs from major U-Joint suppliers like Neapco, Rockford and GMB. No one lists the size required. I did find that it is a very special U-Joint as is the entire drive shaft. Its a design similar to the Mercedes, circa 1990. The Mercedes U-Joint came the closest. Right length, wrong cap diameter. Unless I have a breakthrough tonight in finding one, I'll order a rebuilt driveshaft.

(to mwc0610)

I wish I could find a correct U-Joint to install. Lexus is great but I can't understand why they didn't make this driveshaft more serviceable. At least the new driveshaft will have a new center bearing and be balanced. The center bearing is available on-line at Parts.com for the 1990 thru 1994. I am not familiar with the 1995 LS400 but I assume it has a center bearing too. I didn't see a 1995 listed at Parts.com. Its a little rare but you can probably find it. So many things can cause vibration its hard to pin down, especially if its a driveshaft. My car fooled some real experts that I ddeal with all the time. I couldn't be sure until I had mine apart. But as others have said, try the simpler and cheaper things first. Looks like you did that already though.

For the forum: Any recommendation on a good drive shaft supplier?

Elvis

So the MB piece is close but the wrong cap diameter? Can a wiz on a lathe make some adapters thatll make the caps fit, are they too small or big. How about some or dimensions? Im a manufacturing process major and a firm believer that anything can be adapted to work as OEM.

I also know that a driveshaft shop can make ANYTHING work, ie. hacking both ends and grafting a real Generic spicer U joint girdle to each side!

[pishta]

The bad news is that I cannot find a replacement. I downloaded catalogs from major U-Joint suppliers like Neapco, Rockford and GMB. No one lists the size required. I did find that it is a very special U-Joint as is the entire drive shaft. Its a design similar to the Mercedes, circa 1990. The Mercedes U-Joint came the closest. Right length, wrong cap diameter. Unless I have a breakthrough tonight in finding one, I'll order a rebuilt driveshaft.

(to mwc0610)

I wish I could find a correct U-Joint to install. Lexus is great but I can't understand why they didn't make this driveshaft more serviceable. At least the new driveshaft will have a new center bearing and be balanced. The center bearing is available on-line at Parts.com for the 1990 thru 1994. I am not familiar with the 1995 LS400 but I assume it has a center bearing too. I didn't see a 1995 listed at Parts.com. Its a little rare but you can probably find it. So many things can cause vibration its hard to pin down, especially if its a driveshaft. My car fooled some real experts that I ddeal with all the time. I couldn't be sure until I had mine apart. But as others have said, try the simpler and cheaper things first. Looks like you did that already though.

For the forum: Any recommendation on a good drive shaft supplier?

Elvis

So the MB piece is close but the wrong cap diameter? Can a wiz on a lathe make some adapters thatll make the caps fit, are they too small or big. How about some or dimensions? Im a manufacturing process major and a firm believer that anything can be adapted to work as OEM.

I also know that a driveshaft shop can make ANYTHING work, ie. hacking both ends and grafting a real Generic spicer U joint girdle to each side!

[elvis]

The bad news is that I cannot find a replacement. I downloaded catalogs from major U-Joint suppliers like Neapco, Rockford and GMB. No one lists the size required. I did find that it is a very special U-Joint as is the entire drive shaft. Its a design similar to the Mercedes, circa 1990. The Mercedes U-Joint came the closest. Right length, wrong cap diameter. Unless I have a breakthrough tonight in finding one, I'll order a rebuilt driveshaft.

(to mwc0610)

I wish I could find a correct U-Joint to install. Lexus is great but I can't understand why they didn't make this driveshaft more serviceable. At least the new driveshaft will have a new center bearing and be balanced. The center bearing is available on-line at Parts.com for the 1990 thru 1994. I am not familiar with the 1995 LS400 but I assume it has a center bearing too. I didn't see a 1995 listed at Parts.com. Its a little rare but you can probably find it. So many things can cause vibration its hard to pin down, especially if its a driveshaft. My car fooled some real experts that I ddeal with all the time. I couldn't be sure until I had mine apart. But as others have said, try the simpler and cheaper things first. Looks like you did that already though.

For the forum: Any recommendation on a good drive shaft supplier?

Elvis

So the MB piece is close but the wrong cap diameter? Can a wiz on a lathe make some adapters thatll make the caps fit, are they too small or big. How about some or dimensions? Im a manufacturing process major and a firm believer that anything can be adapted to work as OEM.

I also know that a driveshaft shop can make ANYTHING work, ie. hacking both ends and grafting a real Generic spicer U joint girdle to each side!

Pishta, sorry, I was away from the computer awhile. Always glad when someone else wants to solve these problems too. Here is some data:

Sizes needed for a 1991 Lexus if you are planning to re-stake it:

Required Span (cap outside edge to cap outside edge, called “outside lockup”) 2.929 inches.

Required Cap Diameter: 0.972 Inches

The closest I have found is A GMB U joint (part number 2207284) for a 1990 Mercedes 300 SL

Span: 2.929 inches (OK)

Cap Diameter 0.945 inches, need 0.972 inches (too small)

Here’s a link to the GMB .pdf catalog:

http://www.gmb.net/members/catalogFrame.htm

Here is a link to the Mercedes U Joint that almost fit from Advance Auto Parts. http://www.partsamerica.com/ProductDetail....tNumber=2207284

It looks very similar to the Lexus U Joint I pulled out. Note the rolled edges on the bearing caps on the inside. As far as I know these u joints are only used on a few cars like the Mercedes and the Lexus.

Here’s a link where I found the info on the Mercedes drive shaft. It mentions Lexus as being a similar design. It is a very special design and a very special U Joint.

Link: http://driveshafts.com/pages/mercedes_ujoint.html

Here’s a quote:

“The Mercedes universal joint is quite interesting. Unlike most designs, the roller bearings are contained in a thin shell, stamped from an exotic alloy sheet metal 1 mm thick. It is formed accurately enough to not require subsequent machining and is heat treated sufficiently by the force of the stamping to not require subsequent heat treating. The thinness of this bearing cap allows a large cross and larger roller bearings to be utilized, greatly increasing both strength and bearing life, while keeping size and weight low.”

Glad to hear you are a manufacturing process major! I believe you are on the right track and this problem can be solved. There are other U joints the right length and a slightly bigger diameter. A machine shop could bore the 4 holes required without much problem. If done carefully, I don’t believe the balance would be affected enough to notice. With the right instructions, they could also cut the cir-clip grooves so that staking would not be required.

I had to get my car on the road again so I went ahead and ordered a replacement drive shaft for a little over $400 from PartsTrain.com. I thought at least its better than the $928 from Lexus and my labor is free. It was hard to find. Some companies advertise it but aren’t handling it anymore. I’ll look at the one I get in a few days, especially what the u joint looks like. Maybe it will have a number on it. I will post it if it does. My guess is that it comes from Japan and its made or rebuilt there.

I did look into the cost of a single-piece driveshaft. Not a bad option but by the time you modified each end to accommodate the Lexus flexible couplings, its about the same cost as a rebuilt. I would be careful too about using the couplings on a long shaft. It may need a U joint on each end to accommodate differential vertical movement. Lexus didn’t take the one-piece option because of possible harmonics and vibrations from a longer shaft. Their goal was a world-class smooth, quiet car which they succeeded at.

My son has a Turbo Supra (a fore-runner to the Lexus in many ways). He will probably go to a one-piece. It’s a very similar design to Lexus but it has a u joint on each end rather than the flexible couplings the Lexus has. Our other friend did go to a one-piece and is pushing 650 Hp through it. He isn’t concerned with vibration however.

Elvis

[chrisnisbet]

>>Their goal was a world-class smooth, quiet car which they succeeded at.

Well, when it's not vibrating I'd say you're right. When it is though, it's pretty disappointing. Difficult to rectify too.