I Think I've Figured It Out

[maxed_out]

Hey NC, I will never look at those rotors the same anymore. You made a great point about the screws. I wondered what they were they for and you explaination makes sense.

Just a q. how do you "center" them prior to mounting the wheel? Is there a procedure? How do you know if you are centered?

Thanks in advance.

[nc211]

I'm hoping the screws will do it and the rotors are "true". other than lining up the two screw holes to the hub itself, i have no other idea on how to balance them. i know my rear rotors have the screws installed, and the rear wheels are glass smooth now "thanks to the new tires". But the fronts are definatly out of whack! Now with the bad tires gone, new tires on...it's very easy to tell that it's in the brake rotors. I know it's not any of the suspension parts up there, as they're not even a year old and have maybe 15k miles on them. And they were installed correctly, otherwise the dealership would have caught them, like they did with the twisted rear strut at 20 degrees off center. I think this is just one of those "user error" deals, where we all missed the obvious...right in front of our faces.

anywho, won't be doing the rotors this weekend, as they were shipped from the warehouse in Washington State instead of here. They won't be here until next week. So...it's time to clean the throttle body! The future Mrs. is on a cruise with her family "last family trip" and out of communication...so....it's one quick property inspection...then beer:30 with the Bubba's at the beach and some good ole' fashion garage time!

[nc211]

Holy-Crap Max....I think this might be the answer! Not to just my car....but to that famous Lexus vibration. If my new rotors fix this problem, and the front wheels are 1/2 as smooth as my rears..then those "soft metal, brass" screws are the problem in general. If anyone here has replaced their own rotors, they know those two centering screw threads strip faster & easier than Courtney Love as a Crack convention. So, take into consideration my experience with the rotors having slack in them, and the banging noise from them.

What keeps them balanced?......two, tiny soft metal screws. What feature of any car do you use the most?.....The Brakes. Not what feature uses the most time "gas pedle", but the one you use the most.

Now if 13lb's of torque can stip the threads of that screw....what do you think 80,000 miles of stopping a 4,000 lb vehicle would do to them over time?

Rotors are heavy, may 20-30-40 pounds each. What do you think 1 or maybe 2 lbs feels like, spinning unbalanced? But what do you think that will do to your tires?

Long story short....Here's my theory....

Those who have a vibration they can't seem to fix...check the rotors for those screws. Especially those members who have purchased a used, older Lexus. Because the first owner might have had the rotors replaced at Midas or somthing..where they use the cheaper, non-balancing rotors. Long point, made short...check your rotor screws. Caugh up $20 at your dealer and buy a bag of these screws, and repalce them. I've thought about why use brass screws in such a stress-abused environment, and not steel......brass doesn't rust...ceasing your rotors to your hubs. so, instead of "fixing forever the problem with steel", just accept that once every 80k miles, you need to buy a bag of screws for $20, spend the day...and replace your rotor balancing screws.

If 4 or 5 grams of led weights balance a tire....thing what 1/2 a pound of steel would do?

Hey NC, I will never look at those rotors the same anymore. You made a great point about the screws. I wondered what they were they for and you explaination makes sense.

Just a q. how do you "center" them prior to mounting the wheel? Is there a procedure? How do you know if you are centered?

Thanks in advance.

[ArmyofOne]

Holy-Crap Max....I think this might be the answer! Not to just my car....but to that famous Lexus vibration. If my new rotors fix this problem, and the front wheels are 1/2 as smooth as my rears..then those "soft metal, brass" screws are the problem in general. If anyone here has replaced their own rotors, they know those two centering screw threads strip faster & easier than Courtney Love as a Crack convention. So, take into consideration my experience with the rotors having slack in them, and the banging noise from them.

What keeps them balanced?......two, tiny soft metal screws. What feature of any car do you use the most?.....The Brakes. Not what feature uses the most time "gas pedle", but the one you use the most.

Now if 13lb's of torque can stip the threads of that screw....what do you think 80,000 miles of stopping a 4,000 lb vehicle would do to them over time?

Rotors are heavy, may 20-30-40 pounds each. What do you think 1 or maybe 2 lbs feels like, spinning unbalanced? But what do you think that will do to your tires?

Long story short....Here's my theory....

Those who have a vibration they can't seem to fix...check the rotors for those screws. Especially those members who have purchased a used, older Lexus. Because the first owner might have had the rotors replaced at Midas or somthing..where they use the cheaper, non-balancing rotors. Long point, made short...check your rotor screws. Caugh up $20 at your dealer and buy a bag of these screws, and repalce them. I've thought about why use brass screws in such a stress-abused environment, and not steel......brass doesn't rust...ceasing your rotors to your hubs. so, instead of "fixing forever the problem with steel", just accept that once every 80k miles, you need to buy a bag of screws for $20, spend the day...and replace your rotor balancing screws.

If 4 or 5 grams of led weights balance a tire....thing what 1/2 a pound of steel would do?

Hey NC, I will never look at those rotors the same anymore. You made a great point about the screws. I wondered what they were they for and you explaination makes sense.

Just a q. how do you "center" them prior to mounting the wheel? Is there a procedure? How do you know if you are centered?

Thanks in advance.

You have a good theory there NC, very good, in fact i would write lexus corporate. If in fact the screws are as easy to stip as you say, they are indeed the problem.

put stainless screws in there yourself and save the trouble. i have some rustproof screws (use them on hummvees all the time) i can send you a bag with assorted sizes and you can pick and choose. after thousands of miles in the salty north, they still have no rust, so i doubt they will rust here. we use the to center the rotors on the humvees. the humvees rotors are at the diff instead of inside the wheel. they are on the other end of the halfshafts. it is called a CBS, or Central Braking System.

having done the math, a 12 in rotor turning at 65 MPH is doing approx, 1000RPM. i that rotor weighs 13.5 lbs (thats what yours should weigh) and the weight is off center, then it creates a very bad wobble.

i think you are rigth on track.

Edited January 16, 2006 by ArmyofOne

[RFeldes]

I'm with you and Army............Let us know!!

[maxed_out]

NC, this is really getting interesting now. I talked to my guy that runs a high performance tire and alignment shop. He said he has even seen the rotors be out of balance. He has spun them on his hunter. what a nut! (like us) ended up tack welding to put then in balance. Who would ever think of balancing a rotor? he said very common on lex and cadis becasue of the mass of the rotor and the density of the steel during casting. the rotors can have "hard spots" that throw it off. you can't see them.

I hope we reach the bottom soon.

Maxed.

[SRK]

having done the math, a 12 in rotor turning at 65 MPH is doing approx, 10000RPM. i that rotor weighs 13.5 lbs (thats what yours should weigh) and the weight is off center, then it creates a very bad wobble.

At 65 MPH a tire on these cars (plus or minus depending on size) will be turning around 750 RPM.

All good quality rotors are balanced as part of the manufacturing process, certainly Lexus OE rotors are very well balanced, and that's all I will ever use. If one chooses the "Charging Rhino" off shore brand and finds they produce a shake, well that's your choice, and your outcome, having purchased cheaply. Some barefoot guy standing on a dirt floor is not going to make a quality rotor.

That the rotor should be concentric to the center of rotation is obviously critical. Balancing is useless unless that aspect is controlled.

Edited January 16, 2006 by SRK

[bartkat]

:D

[RFeldes]

You guys are on a "Roll" so to speak. Exciting, and I think you are close. Question? Since NC is "so" close to getting married is his obsession with "screws" starting to affect his rationale? SRK, I understand the "wobble" problem but most concerned about his brass or silver Screws. Am I out of "Align"? Just kidding guys and don't take me seriously. It's important that NC, the "Hammer" has a smooth honeymoon without worrying about his "Screws" and "Bangs" :whistles: Best of Luck to you NC and have a Happy, Happy marriage. Hope I did not offend you.

[ArmyofOne]

having done the math, a 12 in rotor turning at 65 MPH is doing approx, 10000RPM. i that rotor weighs 13.5 lbs (thats what yours should weigh) and the weight is off center, then it creates a very bad wobble.

At 65 MPH a tire on these cars (plus or minus depending on size) will be turning around 750 RPM.

All good quality rotors are balanced as part of the manufacturing process, certainly Lexus OE rotors are very well balanced, and that's all I will ever use. If one chooses the "Charging Rhino" off shore brand and finds they produce a shake, well that's your choice, and your outcome, having purchased cheaply. Some barefoot guy standing on a dirt floor is not going to make a quality rotor.

That the rotor should be concentric to the center of rotation is obviously critical. Balancing is useless unless that aspect is controlled.

oops,i meant that to be a thousand, i was a little buzzed, so excuse the extra zero LOL.

[nc211]

Hahaha!! I don't know what's funnier...the post in general...or the fact that you feared you might of offended me?? ME?? Offend me??? Is that even possible? I'm not even 1/1billionth offended amigo!

Well, I can't argue with SRK on the cheap rotor choices...hence my $34 ea. Car-Quest rotors on the front of my car at the moment. Lesson learned along the way I guess. :whistles: I have just completed my first road trip with the new tires...went down to wilmington for the weekend...260 miles round trip. There is no doubt in my mind that the rotors are the problem on my car. She would shake really really really badly for a few minutes...then a gradual turn in the highway and she would calm down for a few seconds....then straight-away...and the shake would gradually come back...so badly that I had to slow down a couple times. When I would take my foot off the gas and coast...it would lessen a bit "the momemtum was evened out, no throttle pushing the car". Put my foot in the gas...and shake she went! It's not a tire balance shake either, it's not in the steering wheel...it's in the car itself, coming from the front. It's got to be the rotors. Should have the new ones on Wed of this week.

Anywho, cleaned the throttle body this weekend instead. I want to give a piece of advice to anyone preparring to do this......get....a....dremel tool! Especially one with the flixable hose attachment, and a steel brush dremel bit....made the job CAKE! I am going to attempt to post up some pictures of the process..but not sure if they're too big to post. I have a Craftsman All-In-One cutting tool, which acts as many different tools. I've got the 24 inch flexable attachment which made cleaning the interior of the throttle body very very very easy! I used probably 1/2 a can of actual throttle cleaner, mostly to wipe it clean after using the steel brush. Have a shop vac handy, and some compressed air...and it's cake. On a side note....the cleaning of the throttle has made a huge improvement in not only my gas mileage, but in the overall power band smoothness of the car..and the quietness of the car too. I am really amazed! Wilmington is 130 miles southeast of Raleigh. Usually leaves a full tank of gas sitting between the half tank to 3/4 tank mark..closer to the half tank mark. On my way back up to Raleigh..took just 1/4 a tank of gas. I could not hear that engine hum I've mentioned before on my car anymore. And, when I would release the cruisecontrol from 80 mph, coast down to 70, then "assume" my regular speed, the car does not "jump" up back to speed. Before hand it would jump and act like you were flooring it to get back up to speed. Now, it gently accelerates back to the original speed. Cleaning the TB was not hard, and has given me great results!

Now let's see if I can post up the pictures....

You guys are on a "Roll" so to speak. Exciting, and I think you are close. Question? Since NC is "so" close to getting married is his obsession with "screws" starting to affect his rationale? SRK, I understand the "wobble" problem but most concerned about his brass or silver Screws. Am I out of "Align"? Just kidding guys and don't take me seriously. It's important that NC, the "Hammer" has a smooth honeymoon without worrying about his "Screws" and "Bangs" :whistles: Best of Luck to you NC and have a Happy, Happy marriage. Hope I did not offend you.

i need to learn how to resize my pictures. my new digital camera is set at max resolution and 7.1 megpix. can't attach too many pictures....working on trying to fix it.

[RFeldes]

Thanks, NC just worried about YA and my heartfelt concern about your front end. :whistles: Hope you get that problem "straightened" out with the new Rotors before your wedding. I know, I know..don't look for an invitation in the mail. But I really got a kick out of the "Hammer". Best of Luck, Buddy and don't leave us in Suspense....ion? LOL.. HONESTLY, THE NEW ROTORS WILL BE THE SOLUTION!!!

[ArmyofOne]

Thanks, NC just worried about YA and my heartfelt concern about your front end. :whistles: Hope you get that problem "straightened" out with the new Rotors before your wedding. I know, I know..don't look for an invitation in the mail. But I really got a kick out of the "Hammer". Best of Luck, Buddy and don't leave us in Suspense....ion? LOL.. HONESTLY, THE NEW ROTORS WILL BE THE SOLUTION!!!

RFeldes, you are a fuggin riot! LOL.

[nc211]

You know....sometimes a vibrating front end isn't a bad thing.... :whistles:

If those of you reading this one don't understand...then you're too young to ask and go to sleep...it's past your curfew.

Rotors are enroute as I type..they're 40 miles up the road from me. Now if the weather would just cooperate this weekend, I can put them on and settle this thing! If this fixes it...guys...running out of problems..well..with the car that is.

Thanks, NC just worried about YA and my heartfelt concern about your front end. :whistles: Hope you get that problem "straightened" out with the new Rotors before your wedding. I know, I know..don't look for an invitation in the mail. But I really got a kick out of the "Hammer". Best of Luck, Buddy and don't leave us in Suspense....ion? LOL.. HONESTLY, THE NEW ROTORS WILL BE THE SOLUTION!!!

[ArmyofOne]

You know....sometimes a vibrating front end isn't a bad thing....:whistles:

If those of you reading this one don't understand...then you're too young to ask and go to sleep...it's past your curfew.

Rotors are enroute as I type..they're 40 miles up the road from me. Now if the weather would just cooperate this weekend, I can put them on and settle this thing! If this fixes it...guys...running out of problems..well..with the car that is.

Thanks, NC just worried about YA and my heartfelt concern about your front end.:whistles: Hope you get that problem "straightened" out with the new Rotors before your wedding. I know, I know..don't look for an invitation in the mail. But I really got a kick out of the "Hammer". Best of Luck, Buddy and don't leave us in Suspense....ion? LOL.. HONESTLY, THE NEW ROTORS WILL BE THE SOLUTION!!!

dont say that NC, more can and will come as time passes. but its pretty good when you see a forum full of 10 year old cars, and the worst post is about how to change a lightbulb...LOL

[nc211]

I've been waiting a long time to say this.......

It's FIXED!! :D

It was indeed the front rotors! I just finished putting the new ones on "in the pouring down rain might I add". I went for a drive, and the problem is no longer. She does need a balancing job, as there is a slight vibration at 65 mph and up, but not that bad...maybe needs one or two tiny weights. It's probably from the tire stems, it's that faint of a vibration. Probably have her aligned too since these are new tires and all, although she doesn't pull at all. I wanted to take some pictures, but the second I got the first wheel off the car, it started to rain....I just kept on going...neighbors definetly think i'm nuts now! Hahaha.

So as it appears the problem that created this thread to begin with ended up being 1) a twisted strut on the back 2) worn out tires and 3) cheap car-quest rotors on the front "my fault" that did not have the centering screws of which every mechanic who looked at the car, missed. Life is gooooodddd.

"Lookin' good Billy Ray!"

"Feelin' good Lewis!"......quote from the eddie murphy movie, trading places..

[Threadcutter]

I've been waiting a long time to say this.......

It's FIXED!! :D

It was indeed the front rotors! I just finished putting the new ones on "in the pouring down rain might I add". I went for a drive, and the problem is no longer. She does need a balancing job, as there is a slight vibration at 65 mph and up, but not that bad...maybe needs one or two tiny weights. It's probably from the tire stems, it's that faint of a vibration. Probably have her aligned too since these are new tires and all, although she doesn't pull at all. I wanted to take some pictures, but the second I got the first wheel off the car, it started to rain....I just kept on going...neighbors definetly think i'm nuts now! Hahaha.

So as it appears the problem that created this thread to begin with ended up being 1) a twisted strut on the back 2) worn out tires and 3) cheap car-quest rotors on the front "my fault" that did not have the centering screws of which every mechanic who looked at the car, missed. Life is gooooodddd.

"Lookin' good Billy Ray!"

"Feelin' good Lewis!"......quote from the eddie murphy movie, trading places..

nc:

Very Cool!.......Congrats!

Lemme ask you a question though.........Did you make absolutely certain that all pistons in your calipers were free to extend & retract fully? I don't necessarily doubt that the problem was "cheap car-quest rotors on the front", but any rotor will warp if one (or more) of the pistons isn't retracting.

Sorry, I don't mean to "Rain" on your parade. If you've already checked them and are satisfied the pistons move freely, you're all set.

[nc211]

Oh yeah, all the pistons are good. I took care of them a few months ago when i replaced the pads. It's not that the front rotors were warped though, it's that they were not designed with those two mounting screw holes that keeps them balanced when putting on the wheels.

[RFeldes]

"There Is A God !!!!!" Whew!! Congrats, "Roto-r Rooter"

[ArmyofOne]

"There Is A God !!!!!" Whew!! Congrats, "Roto-r Rooter"

haha, i was thinking more along the lines of Mr. Rotor.

Glad to hear you fixed it NC. you should call, ill do a shot with you to celebrate :)

[nc211]

Well.....now I really need those shim kits on the front pads because man....do they SCREAM. Hahaha. But that's no big deal at all, just need some oem pads and 30 minutes. I went and had the tires balanced on the hunter 9700 system with road force, two tires were pretty bad off on the road force, but were fixed, the other two were dead on center. Now I think it needs a proper alignment to set up the car for the new tires, correctly. And then it's just driving it and tinkering.....oh....bought the future Mrs. Roto-r Rooter's LOL, wedding ban yesterday...didn't know she wanted diamonds in that too!

So I told her on our way home that I get to pick out the next car to replace her honda civic.......

can...you...say....daddy...wants....a....IS300 or GS400.

[Threadcutter]

Well.....now I really need those shim kits on the front pads because man....do they SCREAM. Hahaha. But that's no big deal at all, just need some oem pads and 30 minutes. I went and had the tires balanced on the hunter 9700 system with road force, two tires were pretty bad off on the road force, but were fixed, the other two were dead on center. Now I think it needs a proper alignment to set up the car for the new tires, correctly. And then it's just driving it and tinkering.....oh....bought the future Mrs. Roto-r Rooter's LOL, wedding ban yesterday...didn't know she wanted diamonds in that too!

So I told her on our way home that I get to pick out the next car to replace her honda civic.......

can...you...say....daddy...wants....a....IS300 or GS400.

nc:

Just a thought............. & you can certainly tell me if it's none of my business but, didja spend more on the band than you have on parts in the last 12 months?........hehehe .

To be fair about it, Mrs. M. has received far, far and away more shiny stuff SINCE we've been married than what the "band" was/is worth. Let's put it this way; She has no complaints......

All the best, Congratulations! (on getting married, you already got an "atta boy" on the brakes).

BTW; I've been thinking about parts costs relative to the different models. On Park Place's parts website, they will often (generically) list the same part, but for different models. I seem to remember that a starter for example is more expensive for an SC400 than it is for an LS400...................................

[SRK]

Feels good to fix something like that doesn't it? I mean, if it was easy, anyone could do it. But they can't.

Well done.

[nc211]

guys...i was driving to the office today, and hit the very smooth black-top infront of the office, and I am

sorry to report...but it isn't fixed, I'm right back where I started when I first found the club lexus website,

and was brought over here by our good friend bi-col. I don't know what's wrong, I think it might be a bent

rim or two, but, I'm done trying to fix this car. I am very dissappointed in the fact that MY ls400 isn't what

the normal ones are, but I've got to stop the bleeding and call a spade, a spade. I'm selling mine and going

back to Nissan. I know some of you will bark at me for this, but understand, that I have spend thousands of

dollars in parts, and thousands in labor, and a several hundred in tools in trying to figure this out. I spent

last weekend in the pouring down rain working on this car, and now have one hell of a cold to show for it.

I'm sorry guys, but this is one LS400 owner that is throwing in the towel.

The vibration that I felt in the car is the original vibration that sparked the new motor mounts, tranny mount,

and all the other parts in my signature. I'm not going to do this again. Nor am I going to bash these cars, I

just got a POS version, that was clearly not what the dealership told me it was. I know I said I would always

have one of these cars in my driveway. And one day I shall again. Who ever gets this car, will have a 99%

perfect LS400. I am all but convinced it's the rims. But I will not spend another dime on hoping to fix it. I

would rather spend it on a new car. In addition, there is another motive to this decision:

SWO3ES will agree, as will all other economists....when one element goes up, another comes

down...Elasticisty of economy....when gas prices rise, SUV prices fall. Guys, I need something that can haul

stuff. I'm getting married soon, probably going to take a new job in a different city, and in all honesty, I

need a hauler. So, I'm going to tap my auctioneer buddy and f

ind me a fully loaded one of

these...http://www.autotrader.com/

The market is floooooded with SUV's = bad for sellers = great for buyers! Now fellas, we're happy Toyotaians here, but you can't really argue with fact that Nissan doesn't build one hell of a V6 engine! And to

be quite honest, I think they build one of the most user friendly SUV's on earth. I like the 4 runner a lot,

but I hate the driving position of them.

So, in short...anyone want a 1995 LS400, 110k miles, All new OEM control arms, mounts, clean throttle

body, and all the other good stuff below? All she needs is a new set of rims and maybe some top strut

mounts? Oh..and the entire repair manual, including the technician training manuals too. I'm asking $13,000

, but negotiable...to a point ;)

[blake918]

WOOOOH! What a shock! I'm at a loss for words! We're going to miss you, Rob. Nissan does make some great cars (they even make some of them here in MS!). I really hope that things work out better for you with a Nissan/Infiniti! Good luck, buddy!! :D