FYI - I have a 91 940T with Girling front Calipers, ABS

I have developed a problem with the front brakes, I won't call it a shudder because I've had warped rotors before and it does not feel like this. Once per wheel revolution it will feel like I pressed the brakes harder, but just for an instant. I have noticed that this snag is not present until driving the car for a few minutes, so the brakes need some time to warm up before it appears.

It recently failed inspection in DC because the front brakes were "out of balance". This weekend I went through the normal caliper maintenance that I thought would fix the problem.

My first test was to check for a sticky caliper or one-way hose problem. I jacked up the car and spun each of the wheels, they moved freely. Then I had my friend step on the brakes, the wheels stopped, then I had him release the brakes and the wheels once again spun freely.

Next I took of the calipers, relubed the pins (after sanding off a bit of rust that formed around the dust boot), and the sliding contact surfaces between the calipers and the brake pad, and put it all back together.

When I took it out to test the brakes, the snag returned after a few minutes.

Are there any other things that I should be checking? Other maintenance I could perform? I checked out the FAQ, but I need more help.

Thanks,
Mike