CareyPJ

My GS400 has developed a loud noise coming from the front-end. It seems associated with the drivetrain, as it doesn't occur at idle/rest. It seems to be coming equally from both sides, so I haven't isolated it yet.

Could it be a bearing problem?

I haven't had a chance to look under the car yet, but I plan to reomve the wheels this weekend. Anything specific I should look for or try?

Thanks for your help,

GreddyEddy

iTrader: (6)

If you've upgraded your wheels recently? Try changing to a different set of tires or if you have the stocks, put those back on and drive it around. Some tires make alotta noise, that sound like a wheel bearing.

CareyPJ

Thanks for the feedback.

The used car did come with some generic brand tires, so I know they are generating some of the noise, but it seems to have increased. I'm going to check the brakes this weekend to determine if they a dragging.

I'm looking forward to replacing the tires with some name brand soon.

RON430

Sort of late in the day to offer much help but could you describe the noise in more detail? And give a few more details on the car including year and mileage and accident history if you know it. It certainly could be a wheel bearing although it is surprising how bad bearings can be and still not make any noise. It is always difficult to diagnose over the internet but I am not sure there is anything specific that has given people trouble. Some of what has, like the loose front sway bar mounts, doesn't really cause any noise.

Good luck.

CareyPJ

I appreciate your offer to help, although I haven't had a chance to look further into it.

Since we are the 2nd or 3rd owner (we bought the car at CarMax) of this 2000 GS400, I don't know the complete car history. We purchased the car with about 38K miles & it has about 60K on it now. Prior to our purchase, the Lexus dealer mentioned it had non-Lexus front brake pads. At the time, I thought it was a sales pitch, but maybe the pads are poor quality. Beside the generic tires (FULDA), I can only speculate that it is a bearing issue.

The noise is sort of a grinding sound that increase with speed. It doesn't necessarily change with an application of the brakes, but definitely seems associated with some rotational of the front wheels. Anything else to investigate?

GreddyEddy

iTrader: (6)

Mine sounded the same. It made like a grinding noise a about 40mph or coming to a stop. With 90k on the car I thought it was definitely the bearings, but i replaced the brakes first. I could'nt beleive it, but it was the tires. You could always try putting on your spare tire on the driver front to see if some of the noise goes away. It's worth a try. What have you got to lose. When i did that the sound was practicaly gone (about 75%) but still heard alittle in the rear.

RON430

Sorry to not have checked back but been a little too busy. Swapping tires is a pretty quick check. You may not even have to see if the noise goes away, just if the tire change makes it significantly different. More work, but often times more informative, is to do a front to back on both sides. Because the rears aren't turning, they often don't get the unusual wear patterns that the fronts can. Also, if the noise changes depending on road surface, it is probably tires. I would have said it is almost always tires but we threw out the Yokohama AVS db II's on my wife's GS3 because after 18K miles they got extremely noisy and it started to make no difference what the road was like. Unless a brake is dragging or has a hung up pad (which usually doesn't make noise for long) you would have to expect the noise would be more pronounced only when you step on the brakes. That does kind of then put you at the bearing problem. But bearings in Toyota's in general are pretty good. About the only thing that can really get a bearing to go away quick is either something wrong in the motion of the suspension that is inducing a load that shouldn't be there (my 68 L88 corvette ate rear bearings at a terrific rate but that was the vette's geometry) or if the bearing got a thorough soaking. Tow vehicles for boats that can get those rear axles under water a lot can also have wheel bearing problems in situations where they normally don't occur.

Unless you are doing this to learn and find it part of your recreation, the other thing to do is find a good suspenion shop. Often times dealers are not very good suspension shops. I am referring to tracking down a problem on an older car. Dealers are far more oriented to performing under warranty maintenance which involves replacing things at no charge to the owner until you find the problem. That is not meant to run down dealer service problems but a good suspension shop is worth it's weight in prematurely worn tires. You might want to spend some time trying to find a good suspension shop and get their opinion. Around here Custom Alignment is about as good as they come. Both my GS's are under warranty but I take them to Custom to make sure things are done right, the first time. Last time I had my GS4 in, I asked them to do the brakes, I have about 40K miles. They looked and said there was too much pad left (around 50%) to justify a brake job but we talked about pads. Custom has more race cars and high end street hardware go through there (some very mean looking Porsche's, not your average wannabe M or AMG) and their opinion is that they will use OEM pads whenever possible. They have just found that there are less problems with OEM pads than anything else they could install. The brake feel on the GS may not be great but I don't have much complaint about the stock brake pad setup so we are pretty lucky here.

Good luck.

CareyPJ

I just ordered a set of front & rear brake pads (Rotora's Axxis from our sponsor's Carson Toyota). Once I'm going to the trouble of jacking up the car to rotate the tires, I might as well change out the pads.

No, I'd rather spend my limited recreation time out driving instead of maintenace due to the fear of causing further damage to the car as each mile in traffic passing along.

Thanks for the feedback & encouragement.