I recently did the front brakes on my 03 XKR coupe using Centrix rotors and Hawk HPS pads. Cleaned everything up and put it all back together without any problems.

After about 1000 miles or so I've now got a pretty consistent click when coming to a stop. I did notice that the Hawk pads fit a little more loosely than the OEM ones did but I expected that the springs would have taken care of that.

Has anyone else run into this? Thanks!

 

I'll follow up on my own question.

This last weekend I checked everything again, re-bled the brakes and the noise is still there.

I did notice that the pads are a little loose in the caliper, even with the anti rattle springs, so my conclusion is that the pads are shifting in the caliper under moderate braking.

The Hawk pad set didn't come with shims nor were there any with the old set that I removed but have others found the need to use shims with the Brembo calipers? I have the silver calipers and the non-drilled rotors.

 

Never had any shimms, and also never had any sort of issue you mention, and I am already on my 4th set of Hawks and original springs. You could double check the main bolts that hold the caliper. Another suggestion is to have someone in the car press the brakes and running engine let them put the gear into D and R, and check outside if you can locate the noise.

 

I just changed the pads to Hawks and have no rattling. The only spring on the Brembo caliper is the one under the retainer pins. That should be enough. If you have other sounds, it may be coming from somewhere else. Pad changes on these brakes are very simple. Getting the rotors off is another story.... I did find out that the slight imbalance at 70 that I could not get rid of was out of balance rotors. The new rotors track smoothly.

 

I did change the rotors, but when I put it all back together I torqued the bolts per what's in JTIS. They aren't obviously loose but I'll check the torque again.

I didn't put any Loctite on them when I reassembled, and have always done it this way without issues, but this is the first time I've done brakes on this particular car.

What's the consensus, is Loctite needed for caliper bolts on XKs?

 

Do you get any rattle when you drive over small sharp bumps?

 

Not at all. It only happens when braking.

 

I never loctite caliper bolts, but I do torque them to spec, about 135 ft lbs on the Brembos. They won't be coming loose at that torque.

 

CC;

Check this out and see if it gives you any ideas.

Seems this is not that unusual if the Dealers can't get it right either.

JagRepair.com - Jaguar Repair Information Resource

This Bulletin covers your problem.

XK
DATE
02/05
206-11
SERVICE
TECHNICAL BULLETIN
Vibration When Braking (Comeback Visits) – Brembo Brakes – Disc/Hub Optimization Procedure
MODEL 2001 MY-ON XK
VIN
A22191-ON
Issue:
Some 2001 MY-on XKR vehicles may exhibit vibration when the brakes (Brembo) are applied, even after the front brake discs have been replaced. To remedy this condition on a repeat repair, install new front brake discs on the hub flange in a position that minimizes the lateral run-out of the brake disc.
Action:
In case of a repeat customer complaint of vibration when braking, follow the procedure below to install new front brake discs with minimum lateral run-out.
BRAKE DISC OPTIMIZATION PROCEDURE
1. Remove front brake discs (see Global Technical Reference GTR Workshop Manual, section 206-03, SRO 70.10.10).
2. Clean brake calipers and mating faces on hubs.
3. Install the new brake disc on the hub.
4. Install wheel nuts and tighten to 20 Nm (15 lbf.ft).
5. Install a dial indicator gauge and fixture on a suitable mounting point.
6. Position dial indicator gauge 5 mm in from outer edge of disc.
7. Rotate disc one complete revolution and record brake disc run-out.
8. Remove wheel nuts.
9. Carry out steps 3 to 8 to check disc run-out by repositioning the brake disc on the wheel studs in the four remaining possible positions.
10. Install brake disc in the position with the minimum recorded run-out (see Global Technical Reference GTR Workshop Manual, section 206-03, SRO 70.10.10).
11. Carryoutsteps 1to10 for the opposite side brake disc.

NOTE: THE INFORMATION IN TECHNICAL BULLETINS IS INTENDED FOR USE BY TRAINED, PROFESSIONAL TECHNI- CIANS WITH THE KNOWLEDGE, TOOLS, AND EQUIPMENT TO DO THE JOB PROPERLY AND SAFELY. IT INFORMS THESE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR PROVIDES INFORMATION THAT COULD ASSIST IN PROPER VEHICLE SERVICE. THE PROCEDURES SHOULD NOT BE PERFORMED BY “DO-IT- YOURSELFERS.” DO NOT ASSUME THAT A CONDITION DESCRIBED AFFECTS YOUR CAR. CONTACT A JAGUAR DEALER TO DETERMINE WHETHER THE BULLETIN APPLIES TO YOUR VEHICLE.
Date of issue 02/05 Bulletin Number 206-11 Page 1 of 2
Global Technical Reference (GTR) Workshop Manual Information:
Dealer access: https://hub.franchise.jaguar.com Internet access: TOPIx - TOPIx
Parts Information:
DESCRIPTION PART NUMBER QTY
N/A - -
Warranty Information:
Warranty claims should be submitted quoting the information found in the table below. This will result in payment of the stated time and, where applicable parts/miscellaneous expense codes as listed.
Description
SRO
Time
Causal Part Number
Install new brake discs to achieve minimum run-out
70.91.32
1.3 hrs.
C2C 8355
Page 2 of 2 Bulletin Number 206-11 Date of issue 02/05


good luck,

jj

 

So, I think I finally sorted this out.

I pulled the pads out again and what I noticed was that in addition to the usual piston marks on the back of the pad, the paint on the edges was worn off in one spot on each side of the pad. I cleaned the calipers out really well and re-greased everything, this time taking care to lube the sides of the pads and the top and bottom of the caliper where the pads ride.

After several days of use, no clunks, no squeals, no noise of any kind, so I think the problem is cured.

This being the first time I've done brakes on something where the pads move inside the the caliper it seems I left out a fairly important step.

Thanks for all the tips and good advice but as with so many things, the problem lies between keyboard and chair.

 

If you ask "The Rev", the answer would be yes. He had a couple back out on him.