Thump

[gtf]

I have a 2005 lx470, (31,000 miles) which I just purchased from a dealer. Had it certified. The vehicle "thumps" just after releasing the brakes from a stop. Does not do it every time, but often. Very annoying. Sometimes it will thump when pulling away from a stop. I do not see much on the LX message board, but it is all over the GX 470 message board (17 pages!! :o ). What they write on that board describes this problem exactly!! Lexus has a service bulletin on this for the GX, and has been replacing the driveshaft and rear control arms.

Has anyone with an LX470 had a similar problem?

[nc211]

I haven't heard much of the LX or sister version Land Cruiser having this problem "I have an 05 4runner V8". But, what you describe, sounds EXACTLY like what we 4runners/tacomas/GX470's have been dealing with for years. The 4runner and GX are 99% identical mechanically. If you look under the truck, at the back differential, follow the driveshaft up towards the transfer case. You should see where the inner portion and outer portion of the driveshaft overlap. The cause of the thump is that outer sleeve sticking in a forward position "off of the differential". It binds a little, then when you creep forward, it frees itself and slaps the base at the differential. It is annoying, that's all. It doesn't hurt the truck, just ticks off the driver. We 4runner guys buy $10 grease guns and Mobile 1 sythetic grease tubes and inject the shaft about every 10k miles with fresh grease, which eliminates it "but doesn't fix it". If you see little nipple-like points on the driveshaft "called zerks", then you too can lube it. Or, my suggestion, is since you just bought it from a Lexus dealership, it's certified, I'd just take it back and have them fix it. They'll probably just lube it though. However, if you push hard enough, "i'm not sure about this part though", maybe that rear shaft is the same as in the GX series, and they'll replace it with one of the new ones! Eitherway, if you think it's going to drive you insane, I'd take it back to them to at least get the file started that you have the problem.

Me? I don't care for it, but I live with it. My 4runner, thanks to that wonderful V8, is so smooth and quiet, that the positives outweigh that negative. One thing that helps is taking it easy when coming to a stop, or popping it into neutral and coast to the stop. I do that sometimes too, plus, it save gas. Which, now that you've got a Toyota V8, you'll quickly realize how dang thirsty they can get with a heavy foot! But the power....oh sweet jesus....you've got to LOVE that power!

[denslexusgx470]

Practically NC's got it. But you could also try and print up the TSB I posted (I forgot what page it's on, I think I mentioned it in the title) and show it to your Lexus dealer and maybe they might entertain the TSB since you will be dealing with Lexus, not Toyota in the repair.

[gtf]

Hi Guys,

Just returned from Lexus dealer with this problem. They acknowledged that the problem exists with all LX's. Even took a ride in another LX and it had the same problem. They stated that there was nothing that they could do because Lexus has not manufactured a kit to deal with the problem (as they have with the GX). They need to get calls at the national Lexus number to validate that Lexus LX owners indeed have this problem. Then perhaps a factory fix/service bulletin might follow. I will tell you this, this problem is certainly not in keeping with the engineering of the Lexus line (#1 in quality?) and is an embarassment in a truck/car of this stature. If you have this problem, let Lexus know.

[Jim_Chow]

I have a 2005 lx470, (31,000 miles) which I just purchased from a dealer. Had it certified. The vehicle "thumps" just after releasing the brakes from a stop. Does not do it every time, but often. Very annoying. Sometimes it will thump when pulling away from a stop. I do not see much on the LX message board, but it is all over the GX 470 message board (17 pages!! :o ). What they write on that board describes this problem exactly!! Lexus has a service bulletin on this for the GX, and has been replacing the driveshaft and rear control arms.

Has anyone with an LX470 had a similar problem?

This is the famous, well-documented landcruiser rear driveshaft thump. It's caused by stiction of the outer sleeve of the driveshaft. Just pump a few pumps of multi-purpose grease (I use mobil 1 red) into the slip yoke zerk. Also, you should lube the front and rear U-joint zerks. Be careful NOT to overgrease the slip yoke. Reason is, if you pump too much grease into it (it was expand if you do), the driveshaft won't be able to properly compress (it compresses and extends by design as the rear suspension flexes over bumps), so all the suspension pressure goes to the transfer case (BAD!!). For the U-joints, if you overlube them, the grease will start to squirt out the seals. I usually pump in enough just until it's about to start doing this (~6 pumps). You are supposed to lube the driveshafts (front & rear) every 15K miles. My LX currently has 72K mi (owned it since 50K mi) and the driveshaft doesn't thump.

The GX/4runner thump is different. Unlike the problem w/ the GX, the landcruiser one has a well known solution (grease it). GX owners have had their driveshafts changed multiple times without improvement.

[nc211]

The GX/4runner thump is different. Unlike the problem w/ the GX, the landcruiser one has a well known solution (grease it). GX owners have had their driveshafts changed multiple times without improvement.

Actually, the GX/4runner thump is exactly the same, with the same procedure to address it. I use the same M1 red grease, but am always cautious of over-doing the slider yolk zerk, for the reasons you mentioned earlier. I wish I could get a clear, definitive answer to how much you should actually put in there? Jim, have you found any info on this?

[Jim_Chow]

The GX/4runner thump is different. Unlike the problem w/ the GX, the landcruiser one has a well known solution (grease it). GX owners have had their driveshafts changed multiple times without improvement.

Actually, the GX/4runner thump is exactly the same, with the same procedure to address it. I use the same M1 red grease, but am always cautious of over-doing the slider yolk zerk, for the reasons you mentioned earlier. I wish I could get a clear, definitive answer to how much you should actually put in there? Jim, have you found any info on this?

Nope. The first time I did it on my 4runner, I overfilled it. IIRC, I pumped quite a bit in, maybe 12-15 pumps before I saw it start to expand. The remedy is to remove the zerk, then drive over some speed bumps or down the curb a few times so the excess grease can ooze out, replace zerk. I've only used about 4 pumps of M1 grease on the slide yoke and about 4-6 pumps on the U-joints (just until I can see the old grease start to ooze out) every 15K miles. So far, no thumping at 72K mi. BTW, the LX driveshaft was redesigned in '03. I know the diameter was increased (according to Slee's website), don't known if the types of metals were changed or not.

[zandango]

Hello

I have an 2003 LX, bought with 9000 miles just about 5 years ago, it now has over 101000 running fine, I hear the thump 20% of the time at starts and sometimes stops, I talk to the dealer many times, they all say it's normal, I regularly have it serviced, and lube by the dealer.

I have also talked to a local mechanic, who is very familar with the noise and said that's they whey they are built.

B)

The GX/4runner thump is different. Unlike the problem w/ the GX, the landcruiser one has a well known solution (grease it). GX owners have had their driveshafts changed multiple times without improvement.

Actually, the GX/4runner thump is exactly the same, with the same procedure to address it. I use the same M1 red grease, but am always cautious of over-doing the slider yolk zerk, for the reasons you mentioned earlier. I wish I could get a clear, definitive answer to how much you should actually put in there? Jim, have you found any info on this?

Nope. The first time I did it on my 4runner, I overfilled it. IIRC, I pumped quite a bit in, maybe 12-15 pumps before I saw it start to expand. The remedy is to remove the zerk, then drive over some speed bumps or down the curb a few times so the excess grease can ooze out, replace zerk. I've only used about 4 pumps of M1 grease on the slide yoke and about 4-6 pumps on the U-joints (just until I can see the old grease start to ooze out) every 15K miles. So far, no thumping at 72K mi. BTW, the LX driveshaft was redesigned in '03. I know the diameter was increased (according to Slee's website), don't known if the types of metals were changed or not.

[jasonhavens]

We have the same issue with our 2003 LX 470. It's certainly disappointing that Lexus is approaching this kind of well-known problem in this way. I just posted in response to another topic (02 Lx470 Driveline Clunk?) of this forum. Any help/suggestions are welcome.

[jasonhavens]

Based on my research on these helpful forums, I am now convinced that this is the same issue as the GX model. Attached are the highlighted technical service bulletins for both the 2003 GX 470 and LX 470, where Lexus has clearly acknowledged the problem with the GX but not the LX. I plan to write a relatively strong letter to Lexus "suggesting" that they resolve this problem. I hope that you and others do the same. Maybe I should post my letter here so that others may see it.

Kind regards,

Jason Havens

Destin, FL

I have a 2005 lx470, (31,000 miles) which I just purchased from a dealer. Had it certified. The vehicle "thumps" just after releasing the brakes from a stop. Does not do it every time, but often. Very annoying. Sometimes it will thump when pulling away from a stop. I do not see much on the LX message board, but it is all over the GX 470 message board (17 pages!! :o ). What they write on that board describes this problem exactly!! Lexus has a service bulletin on this for the GX, and has been replacing the driveshaft and rear control arms.

Has anyone with an LX470 had a similar problem?

TSB for your 2003 Lexus Truck GX 470 V8-4_7L.pdf

Find Technical Service Bulletins for your 2003 Lexus Truck LX 470 V8-4_7L.pdf

[johnlx470]

I also suffer from this issue. it has been driving me crazy! it only started in the last couple of months. I was really worried it was a tranny issue.

[TheCat1]

I have a 2005 lx470, (31,000 miles) which I just purchased from a dealer. Had it certified. The vehicle "thumps" just after releasing the brakes from a stop. Does not do it every time, but often. Very annoying. Sometimes it will thump when pulling away from a stop. I do not see much on the LX message board, but it is all over the GX 470 message board (17 pages!! ). What they write on that board describes this problem exactly!! Lexus has a service bulletin on this for the GX, and has been replacing the driveshaft and rear control arms.

Has anyone with an LX470 had a similar problem?

I was experiencing the same problem in my 2007 LX470 thump when foot in removed from the brake pedal in drive and the service manager at my Lexus dealer test drove my LX and said it was the drive shaft and ordered a replacement under warranty and it solved this problem. I had taken it in for a vibration problem at highway sppeds and he said it was tires bit after replacing three sets of Dunlops tires within the first 3,000 miles I have been living with the viration fromblem since 2007 and installed a set of Yokohama Geolanders at 38,000 miles. The service manager determined that the vibration was caused by the drive shaft and replaced it solving the vibration problems and my LX now drives beautifully for the first time since 2007. So don't give up with either of these issues keep on your dealer service manager until they replace the drive shaft under warranty. This is a known problem in the GX model and now on some LXs.