89 W126 560 SEC Vibration In Brake Pedal When Stopping
 

Hi All,

I had a vibration in the brake pedal when stopping and I figured that like most cars vibration in pedal is rear rotor, vibration in steering wheel is front rotors.
The car had to go to Me/Be to get the lambda set so I asked them to check and they said rear rotors.
I changed the rear rotors and pads and I still have that vibration in the pedal. I decided to change the front pads a month after that even though they were still good so I had a time that all pads were done.
Do I need to get the rotors cut or can it be something else?

Thanks
Jack
1989 560 SEC
1980 450 SL

Ckeck the " run-out " on the front rotors & the thickness. ;)

When they change your tires with the air guns set to high it can warp the rotors and cause the vibration through the pedal. The last time it happened to me it was the front rotors. Did not have enough left on the rotors to true so I had to replace them.

Have them check it for end play in the bearings.

Remember those cars have adjustable front hub bearings which can need tightened up a little bit.

Sometimes when the tech replaces the fron rotors and packs the bearings, they dont seat the bearings right and do not gauge them for end play.

It is usually noticeable right away, but sometimes may rear its ugly head as a vibration if the bearings get worn.

You may be able to repack the bearings and snug them up a little bit.

Check it yourself.

jack the front end up and put a jack stand under the frame.
then grab the lower and upper portion of the wheel and wiggle it back and forth and see if you feel any play or wobble in the wheel.

it's a simple test and can tell you alot about the wheel bearing condition.

Cudaspaz.

This is very real. A shop I once went to in Atlanta had no air tools in the wheel/tire area. I commented on this - and they told me about how they had to buy a customer 4 new Jaguar rotors because of warping. As told to me, most European car rotors are generally made with less meat (less unsprung weight) and are considered disposable - not turnable.