RON430

[QUOTE]Originally posted by GS430lvr

Quote:

Originally posted by RON430
If you believe that then I can guarantee you that every BMW has the same "design" flaw.

Seriously, if you search the extensive other threads you will see a lot of discussion of this. When it showed up on my bimmers years ago I would take it to the dealer who would do something (probably not much, that is when I found out that they didn't do any alignment work but used a local tire store) but never cure it. I went to Custom Alignment and they refer to the steering wheel shake at 55 to 60 as bimmeritis. A good balance will make it go away but it will come back. The lighter weight and more responsive suspensions are more sensitive to balance and "roundness" issues. The heavier rims and tires you hang on a lighter suspension, the more susceptible it is. For me the answer is a very good alignment shop, and not just what equipment they have. Just a price to pay for these sensitive suspensions. [/QUOTE

I agree, my dealer told me I just needed a balance. Regardless, it's got to be an attenuation that's somehow amplified at that 55-60 speed. Mine is the worst when the tires are cold due to flat-spots. I've heard of "bimmeritis" but never experienced it with my father's 97 540i...it was always smooth as glass.

I do believe, however, that the wobble can be lessened or eliminated by appropriate design and engineering. We'll see with the next gen GS.

Vibrations at certain speeds mean that there is a rotating mass that is inducing it. Very likely there is a resonance at one speed that amplifies the effect dramatically. For whatever reason, every bimmer I ever owned would develop the problem and yes it was right around 55-60. Considering that the rotating masses on the car are the tires, wheels, rotors, and hubs, it would seem pretty logical that it comes from one or more of those pieces. The larger diameter the the component, the greater the moment arm and the greater the effect. Also, the greater the mass located at the outer moment arm, the worse an out of balance situation will be. So if you go down the list and take the diameter/mass into account, the vibration would be most prone to the balance (or out of balance) of the 1) tire, 2) wheel, 3) rotor, and then down to hubs and axles, etc. This isn't brain surgery. Obviously, the tire/wheel is the biggest actor in this play. If you want Lexus to design this out in the next series the only way to do it is to make the moving suspension components less susceptible to moving, greater mass and higher friction at movement points to resist vibrations coming back up through the steering by dampening the response of the suspension to the movement of the tire/wheel. I doubt you would like the result.

My problem was not so much the vibration, it was the "wall jobs" I got at bimmer proclaiming to fix it. Once I went to a good independent shop, I could get rid of it. But, as I said, it would always return - took about 3 to five thousand miles. While every bimmer I owned (three fives and two sevens) had this problem, my GS has yet to experience it. I am coming up on 30K miles and, also once again, I have stock 16s which are probably a lot less sensitive to this than larger diameter wheel combinations. I would be all on Lexus to fix it if I thought they could but this is not something they will be able to do much about. Expecially with the trend to lower profile tires and larger wheels. And if you have changed wheels/tires, well, you are on your own.

Now something a manufacturer can do is look at wheels. A friend of mine has a new (well around ten month old) 745 and he has bent five rims. That is ridiculous and something bimmer needs to look at. I don't think roads are especially good in Cali but we don't generally have the pot holes of back East and how exactly my friend keeps bending those rims (18's, I think) is baffling and yes, he is getting tired of paying for rims and is getting tired of the whole car. Bimmer would only replace them for a defect in materials or workmanship, neither one of which they said was the case.

PS, more than once, I had to have the tires trued on the bimmers to make the problem go away and the shop I use can do that. On the bimmers, once it started to shake it would just progressively get worse so whatever was throwing it off would keep adding up, it really didn't stabilize. Once I got to the point of getting very annoyed at the steering wheel shake, I would have to take it in fairly quickly.

Kbueno

RON430- Great info! Lexus should find a solution...if not in the suspension but perhaps in the steering. I've never liked the steering in the GS...feels numb and loose. Obviously, the resonance is transmitting to the steering wheel thru the suspension. I can live with mine...it's only slight and I usually don't travel at 55-60...too slow.

If a rim is bent, wouldn't there be a wobble throughout the speed, becoming progressively worse?? Seems hard to believe that a bent rim would only be noticeable at the 55-60 mph range. There's more going on than that.

RON430

You are definitely right, a bent rim will induce a vibration at all speeds but so will an out of round tire or an out of balance tire. The steering does do some filtering of the feedback. But when the tire/wheel starts spinning up to higher speeds you have effects that can both increase and decrease the vibration, because now you have an unbalanced mass inducing a vibration at varying frequencies related to tire speed. For whatever reason, a resonance happens at that wonderful 55 to 60 spot that markedly increases the amplitude of the vibration. Like I said, I haven't had the problem on the GS but every bimmer had it. If you speed up to 70 or so, it went away, if you slowed downl, it went away. So it was right at the worst spot for most of us. My gut says this problem is only going to get worse as we go to larger wheel sizes and lower profile tires which is the inevitable trend. I just hope I can always find a good suspension shop that can make it go away for a while. No intention of switching to a pickup to avoid this, just have to keep those tires balanced. On the bimmers, once it started, if I didn't get it fixed pretty soon, I would wind up with one or more tires out of round and then it was more costly to get fixed.

Would I like Lexus to get rid of this by making the steering less prone to feedback? No. If something is that out of whack, I want to know about it and get it fixed. That may not apply to everyone but I can't be that much more **** than most of us here.

bitkahuna

iTrader: (20)

If you want smooth no vibration ride, stay with factory 16's.

RNM GS3

Will getting the alignment done to my car help to tighten up the steering on my car?

I feel its getting worse and worse everytime i drive it.

Kbueno

RON430-

Good discussion...but let me clarify the steering issue: I want Lexus to re-design the steering set-up so it's MORE responsive with more feedback and no attenuation at 55-60 with the suspension. I know..I'm dreamin.

bitkahuna-

I have FACTORY 17s! Seems like Lexus is unaware or doesn't care. I would definitely not mind as much if I put some 20s on and then had some vibration.

The vibration is there, it's slight, and I can live with it...but it is still not right!

RON430

Yes and (more likely) no. If the suspension is so far out that it is wandering all over and the steering is being used up trying to keep it going straight, an alignment will make the steering a lot better because you won't be using inputs to keep it going straight. But I find it hard to believe that your car would be in that bad a situation unless you spend most of your time driving bouncing off of curbs and parking bumpers. If by "tightening up" the steering you mean removing play around straight ahead, I am not sure there is much that can be done. Usually the worst situation is with some wear in the steering that induces a poor center feel. The car is tracking straight and it seems to take a fair amount of turn of the steering wheel to get the front wheels to turn sort of thing. Might want to let Lexus or a good shop take a look at it. If you just go in and ask for an alignment, that is what you get. If you go in and say the steering is sloppy, they will tend to look for it.

bakermr

Was having the same wheel shake problem with my new 2003 GS300. Balancing and alignment only helped slightly. My dealer suggested swapping out tires to a tire of my choice. My research indicated Bridgestone Turanza was a great tire so I swapped the Goodyear’s for Bridgestone. The shake is gone. Wheel noise is down. Ride is softer, but performance seems better than ever. Grip is awesome. And the dealer did all this at no charge. Great mid-western commitment to customer service here in central Illinois.

bitkahuna

iTrader: (20)

As tires wear, they get worse. Only solution at some point is replacing them. Lexus does say the tires on the 17's are only good for 15K.

Pearlpower

iTrader: (2)

Could be the hubcentric issue from your spacers as some have pointed out. Bad suspension component (lower ball joint and upper control arm are problematic on GS's) , balancing,design issue, or a combination of these.

ALSO

There is a TSB from Lexus that addresses this issue. Depending on your VIN, you would need the new updated balljoints (this is what I got at $70.00 each), or new ball joints and steering rack bushings, or new balljoints and the bushings and a steering rack saddle. The bushings and saddle require the rack to be removed from the car. Take you VIN to you dealer and ask them which of those 3 options you need. This will eliminate the vibration forever. In my case the ball joints were very wore anyhow, so I went ahead and replaced them with the newer updated versions from Lexus. HUGE difference. Even though Lexus calls for the bushings to be updated for my VIN along with the ball joints , so far I have had no vibration what so ever with just replacing the balljoints. Also keep in mind that the bushings and saddle update will stiffen up your steering a little.

Updated balljoints-$70-$115 each at your dealer depending on your discount.
Install Time: 10 minutes each side if your good and have the proper tools. 20 for average Joe
Difficulty: If you can change brake pads, you can change your balljoints. Very easy job.

With over 3000 miles, still no vibration at 60mph or 80mph-the problem spots. Smooth as butta. Completely different car. I am also running 18 hubcentric wheels. Fixed the problem when I had the factory 17's on. Two sets of 18's after that and still no vibration. I may still do the bushings to stiffen up the steering as the updated ECU did nothing for me.

Every BMW I had has had this issue with very little to do to alleviate it. One of the reasons I stopped buying BMW's. The GS at least has a remedy.

Don't forget a new alignment afterwards

bitkahuna

iTrader: (20)

One thing easily overlooked is tire pressure. If the tires on my hubcentric HRE's are at 32psi (cold), I can get some shimmy at 65 when the tires are cold. It does smooth out after a few miles though. If I put them up to 37psi (cold), there's almost zero vibration when stone cold and it's glass smooth after a mile or two.

RNM GS3

My tires only have about 5k.

Anyway I fixed the problem by balancing my tires/wheels on the Hunter GSP9700 machine. You can go to their site and look one up thats close to you. Thanks to Angel about telling me about this.

Letsride

Whats the web site?

DaveG

[QUOTE]Originally posted by Pearlpower

There is a TSB from Lexus that addresses this issue. Depending on your VIN, you would need the new updated balljoints (this is what I got at $70.00 each), or new ball joints and steering rack bushings, or new balljoints and the bushings and a steering rack saddle. The bushings and saddle require the rack to be removed from the car. Take you VIN to you dealer and ask them which of those 3 options you need. This will eliminate the vibration forever. In my case the ball joints were very wore anyhow, so I went ahead and replaced them with the newer updated versions from Lexus. HUGE difference. Even though Lexus calls for the bushings to be updated for my VIN along with the ball joints , so far I have had no vibration what so ever with just replacing the balljoints. Also keep in mind that the bushings and saddle update will stiffen up your steering a little.
QUOTE]

All these posts about front-end vibrations (mine included) and finally someone finally posts that there is a TSB on this? That's what makes these lists great.

Anyone know what the TSB number is and if there is anyplace on the web to read it? I want to be educated before I go talk to the dealer about it.

TIA

DaveG
03" GS3

RNM GS3

Sorry about that.

Here it is: http://www.gsp9700.com/