I got new rear pads and rotors last week installed in a local shop. Yesterday I noticed a weird smell, but tought the pads are just setting up. Today driving in heavy traffic in the highway a fine gentleman in the right lane got my attention and pointed at my rear wheels - low and behold the right rear wheel was smoking - bad smell everywhere. The left rear brakeseems fine

Any ideas what those guys did wrong with my rear brakes?

 

I had this happen to me once after changing my pads and the rotor. I had neglected to bleed my brake fluid and the fluid was old and causing the caliper piston to not release properly. This caused the pads to drag on the rotor.

If they did not bleed your system you might try that, or even if they did I'd bleed that caliper again just to be sure. There may be some issue/damage with the piston(s) in the caliper. They could have caused some damage when they were reseated?

Hopefully it's something simple...

 

I suggest having a specialist replace rear pads, they require some special knowledge since the electronic parking brake has to be reprogrammed after piston retractionwith a procedure. I imagine your local brake guy messed this up and the brakes are dragging. Flat bed it to the right place, don't drive it. If you want the procedure, go to Alldata.com, it's too much to type. If you roast the caliper and rotor, you will be replacing it at a healthy cost. You can even damage the hub seals from the fire that can result (yes, pads will burn). These cars are way more sophisticated than 95% of the cars out there, most things require special knowledge and tools, this is one of them.
Brian

 

I should have mentioned, this car is so specialized, if you are taking it to a non-jag shop for anything, eventires, take a print-out from alldata.com for the procedurewith you. For example, a simple coolant drain and refill requires removal of a special bleed plug to prevent an engine-dangerous air lock in the cooling system. Even the jacking points are unique and lifting it wrong can smash your expensive undertray and require replacement of this $800 item, tire guys have messed up a lot of these already. It's hard to get the tire guy to spring for a new one when they hear the price! Be warned.

 

Thanks all.

I was back in the shop yesterday, they took the brake apart, could not find anything bad with it- the piston booth was ok. The rotor had slight rainbowl color - which is evidence of it getting hot, I drove it over 5 miles and it was the same temperature as the other one.

The wheel would spin by hand - no dragging noise. I asked them to blead the brakes again as rsculthorecomended - i'll keep an eye on it.

oldsmot - for the parking brake procedure, I know what you are talking about, but this was necessery if you replace the calliper, the jag manual does not mention it when you only replace the pads/rotors - I might be mistaken. Also for the undertray you are right it is broken - the right one, I guess the previous owner was using some local shops as well. I found it for $130 and another $40 for the mounting bracket - thanks to hlgeorge for the parts catalog in the other thread.

 

Quick update: 300 miles and a week later no issues. I take small trips 10-20 miles and check the temperature on the rear wheels every time I exit the car - both wheels seem to heat evenly.

Crossing fingers, bleeding the brakes fixed the issue.

 

I have no idea how the parking brake actually works, it has a computer in it and God only knows what it is calculating and whatsoftware parametersit works with. I do know that when the piston is screwed in at pad change or caliper replacement, the brake needs to relearn where the pads are. New calipers and new pads require the pistons screwedall the way in. Bleeding the brakes changes no settings that would affect the parking brake that I know of, it just takes out the old fluid and puts in new, minus any air bubbles. I have recently bled the brakes and the parking brake was fine.

 

oldsmot, I agree about the parking brake - it is a misterious beast. Every time I disconnect and re-connect the battery it asks me to press the brake pedal. It does have a mind of it's own.

The problem I had was more likethe piston was stuck and would not release properly - what rsculthodescribes. I drove the car for about 100 miles before this happened - I would have noticed if the parking brake was not releasing. Also it happened in the middle of trafficafter 8-10 miles - if it was parking brake it would have started to smoke sooner.