JNeezy

Alright fella's, my problem has perplexed me since getting my Lex. Since I got it it has always had a couple of noises which I have been able to locate and figure out.

1. Differential mounts - gone. Completely. Causes thump when accelerating because the diff twists and hits against the mount where the rubber used to be.

2. Front end - lower ball joints, clunking when driving on rough road surfaces

Now this last one, I thought I had figured out.

3. Rear end thump. Both L and R carrier arm bushing were shot, and by shot I mean there was nothing left. No rubber.

Replaced both of those bushings and my car still has this thump and the rear feels like it's jerking and it happens at ANY speed. There is a slight (very slight) pulsation in the brake pedal. I read in a thread that it could be something wrong with the ABS so I removed the relays/fuses to do a test and it was still there.

I believe it has the original rotors on it. I checked the brake pads, like brand new. I had the vehicle up while I changed the bushings and the rotors didn't feel warped, no waves, no grooves. The thump is loudest in the rear of the drivers side.

Any ideas?

-JNeezy

PureDrifter

iTrader: (10)

did you check the tires...?

trukn1

Something that is often overlooked and even I wasnt aware of it myself until it happened to me,,,,,check the differential bushing at the driveshaft. Chances are it may be worn severly. This would be more centrally heard and not isolated just to one side.

Also items to check would be the upper and lower control arms in the rear; along with their respective ball joints..

JNeezy

Tires are newish.

JNeezy

The bushing that hold the diff to the rear member are shot. That causes a clunk when hitting the accelerator. This is just when braking at any speed really. And it is mostly felt on the drivers side rear.

-JNeezy

PureDrifter

iTrader: (10)

i meant for bubbles/separation and balance.

JNeezy

Yep. Been over every inch of the tires in the back. As I said, they are newish (year old, minimal mileage). I felt the rotors, no waves, no pits or grooves there either. The brake pads, which I thought were the problem originally, are like brand new themselves.

Like I said, it seems to be coming from the drivers side. Thing is, and this made me suspect warped rotors and prompted me to examine them, is how it feels like it's grabbing-letting go-grabbing-letting go until the vehicle comes to a stop. This can be felt in the brake pedal very slightly as well. Could the caliper be shot?

turbo556

Ive had this happen on two cars...check the brake fluid and change it for new fluid....brake fluid is hydrophillic so it attracts water over time.....and dirty bake fluid will cause your brakes to semi engage when the fluid heats up (more pressure since theres water heating up in there as well) and at higher speeds it'll cause a "shudder" or vibration...yet when I swap new brake fluid in the reservior...shudder is 95% gone...Ive had it happen with my Lexus and with a Mercedes....

JNeezy

I'll have to check that out and consider changing the fluid. My radiator just failed on me and the stuff that came out of it made me realize that it has prolly never been changed once in the life of the car. I would not be surprised at all if it had water in it to be honest.

Thanks.