JAG IRS brake shudder

[RICK LAKE]

ollykiwi3 Olly I got a real problem with this problem. I have never had calipers cause a braking problem unless the sliders where no good. Brake pads will cover a number of problems.
I believe you said this has been happening for a long time. I am thinking you have a hard spots in the rotors or rotors. Take them to a machine shop and have them resurfaced. Tell them you want new bits on the machine and the main shaft checked for true. Less than .001" on the brake machine. Resurface both rotors. Clean both stub axle surfaces with 3m wheel. After cleaning install your dial indicator on each stub shaft and check for out of round. Both should be under .002", if not have machine true. Install the rotor and recheck the out of round with the rotors bolted to the stub axles. Again shoudl be less then .002" I checked my jag set from XJ6 and I have about .0017" play all the way around. My does 95% track and auto cross. New pads and same rotors I installed back in 98 and then change pads and resurfaced rotors in 2006. I would change the rotors if nothing shows up. China steel is crap. If this doesn't fix the problem, Go to Jag and find a good tech and see what he said. Can you go 20-30 in reverse?? See if the schutter is there. What happened with the parking brake test?? This should give you the same feedback as rear brakes?? Good Luck Rick L. Ps have an old service manual for Jag, going to look up info and see if any thing will help.