2001 S-Type Auto 51k miles. The car had a vibration when braking so I replaced the front rotors (they were the original rotors at 51k miles). My wife drove the Jag today and said the vibration is still there when applying the brakes, but not as bad and with normal braking. After replaced the rotors I took it for a test drive and several times from 60mph I applies hard braking and there was no vibration. Any suggestions on where the vibration is coming from ?

 

Inspect the steering rack mounts and tie rod ends. Also inspect the upper and lower ball joints for excessive wear as they're known failure points.

 

Thank you. I will inspect those points.

 

N.B. Don’t apply hard braking with new discs and pads. They should be bedded in gently to avoid the pads glazing and the discs warping.

Query: did you replace all 4 discs (rotors)? Or just the fronts?

I totally agree that you should check all steering and suspension joints for play.

Now, I know this sounds misogynistic, but are you sure about the vibration being real? I had a similar situation with an unnamed female I know claiming the brakes were juddering. I drove the car and they were fine. Turns out she wasn’t used to the car and was stamping on the brakes hard enough to activate the ABS making it feel, in her parlance, ‘juddery’.🙄😂

However, there is one other possibility; if all suspension and steering joints are ok, check your shock absorbers. A dead shock can leading to wheel tramping (unregulated bouncing). This could feel like a low frequency vibration.

 

Sportston brings up a good point. If you didn’t feel it on your road test perhaps something thing get lost in translation. Had a customer say the brakes were pulsating after the pad and rotor swap. Turns out they meant the stiction at very low speed very light breaking in parking lot type maneuvers where the pads grip and release making a gunk, gunk type sound as the car inches forward. (This is more common on cars with high performance type brakes and sometimes a consideration when upgrading to more aggressive pads. It wasn’t until I got a full description of the circumstances around the “fault” that they didn’t mean pulsation at speed from “warping”.

 

Thanks for that information. I did check the vibration myself after my wife complained about the vibration and determined it was coming from the front of the Jag and that is why I only replaced the front rotors. I will add the shock absorbers to my check list.
Thanks

 

i had a very similar problem and replaced rotors and pads. It made it better but found a caliper slightly sticking. I raised the car and spun the wheels and found it that way. Not real bad but got worse when the brakes were hotter after a drive. Replaced the caliper and all is good

 

Thanks, I would not have thought of a stacking caliper. I will check it out.