I am currently the owner of a 2011 XJL, with just under 70k miles on it. It's a CPO, purchased in 2015 with 47k miles, at which time the dealer installed new Pirellis. At 60k miles, I had new brakes installed (by a local mechanic whom I trust implicitly). He at first just turned the front rotors, but subsequently replaced them. Since that time, I have had a problem with what I call "pulsing" when I'm braking. It manifests after I've driven quite a bit, and at times is very noticeable via feel as well as shimmying in the steering wheel.

My mechanic tells me the rotors are within .001" of true. He advised me that my left front wheel was bent, so I replaced it with factory new (not refurb - $850!). The car is noticeably smoother riding, yet the pulsing is still there.

I've had a complete alignment and balance; the front wheels twice (three times for the left, when the wheel was replaced).

I despise Pirelli tires (I've never had a set last through its tread without issues), but neither my mechanic nor the tire guy have suggested there are any issues with them. I can't rotate them because the sizes are staggered.

I'm at a loss at this point. Does anyone in the group have a suggestion as to my next move? Short of selling...(that could be the ultimate solution...)

 

Out of round is not the same as excessive parallelism. This is usuallly the issue with pulsing not out of round. This is usually from parallel high spots when a car sits a bit and the rotors develope surface except where the pads sit on the rotors. When you drive the car yes you clean the rust off the surface when braking. Which is now thinner but the spots the pads sat. They had no rust so now that area on the both opposing sides are now "high spots" which creates a pulsting pedal when brakes applied. This is not the only reason but the most common i see. To check you have to measure runout on both surfaces and mark the high spots on each surface.

 

If it feels like braking with a warped disk (or rotor, for Americans ;D), but intermittent, check the front bushes. In particular the inboard front lower arm (the big bush).

 

kent,
If I were you, I would replace the rotors with the OEM rotors, after market rotors could warp after a year.

 

Reyesfam:

The rotors were installed January 18th of this year; runout was checked May 11. I misstated it - it was measured at .0005, still well within tolerance.

 

Failing wheel bearing is another possibility

 

Rotors don't warp.

You can fix the pulsating issue by "seating" your brakes. Find a road that you can drive straight line and get up to 45 or so and safely brake very hard without endangering anyone. Get up to 45 and brake HARD down to around 5, let off the brake and repeat. You may need to do this a bunch of times and you may/should smell the brakes getting very hot which you need to do it right. This process cleans off pad material that has transferred to your brake rotors usually due to incorrect braking techniques. I have fixed many sets of rotors this way back to perfectly smooth.

For future reference do not brake late, hard and then leave your brakes where the car stops. Allow the car to creep forward a bit to avoid pad transfer material.

 

JagGate:
I'll give this a go... For reference, I think of myself as an "easy braker"; easing up to traffic lights, allowing creep after the stop, etc., as much as possible. TBH, I was actually surprised that the car indicated it was time for new brakes before I reached 60k miles (for comparison I changed my 2004 XJ's brakes at 133k).