Hi guys.... love the forum but this is my 1st post. I recently had the front wheel bearings changed as o had a rumble and vibration from the front wheels. The garage informed me that the two front brake calipers were also binding. I plan on getting these replaced this montj but i just wanted to check.... could this be a problem with the abs block ? I find it unusual that both would be binding rather than one or the other ??

Thanks for any help guys !

Duncan

 

May just need them bleeding. It will not be the calipers but the pads that are binding.

Roger

 

OK here are some random thoughts about your problem.
The ABS could possibly be causing the binding, but I d not believe it is a fault in the ABS unit.
A few questions:
1. Did you have a binding problem before the bearing change?
2. Do you know if OEM bearings were used?
It is quite possible that the bearings used are incorrect for the vehicle. I will have to search but there is a write up in the X400 forum showing aftermarket bearings with the incorrect number of triggers for the reluctor that signals the for the ABS.
If the ABS is reading the front wheels as going faster than the rear wheels then YES the ABS will try to slow down those wheels.
I think you have a bearing problem and not a caliper problem.
I would ask your shop to provide you with the info for the bearings used and then get one and get an OEM for comparison and count the triggers for the reluctor.

 

I was able to find the thread. You might want to read this.I only disagree with the conclusion that with less magnets the wheel would be slower. I think the impulses would make the ABS see it as a faster wheel.

https://www.jaguarforums.com/forum/x...ferent-176738/

 

It is possible that they have put the bearings in the wrong way as the reluctor ring is integral with the bearing. If that was the case there would be an ABS fault and EML as the system would not record the wheel.

Roger

 

If the front wheel bearings had less magnets in them, you should still be getting some form of speed sensor error. Besides, you can verify this condition by simply taking the car out on any highway and measuring the time it takes the vehicle to go 1 mile. You simply take the number of seconds it took you to drive the mile, divide it into 3600 and that will give you the MPH. If your speedo is reading close to that, then you have the correct number of magnets. If you have say a 20ish percent error, then you have the wrong wheel bearings. But then, having a 20 percent speedo error should be pretty obvious as you would be doing an actual 72mph when the speedo says 60.

The other thing is that if the wrong bearings were installed in the front wheels, the computer would see the wheels spinning slower, making the computer think that the front wheels are locking up. This would then reduce the applied brake pressure to the front wheels to essentially zero (since the computer would reduce the brake pressure further and further in an attempt to reduce the wheel slippage). This should also result in an error code. Not to mention it should be fairly obvious to the driver that the car requires a significant amount of brake pedal pressure to make the car stop like it used to.