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1979 Trans AM Rear Disc Brakes?

Gary Smith

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Please let me know if this has been covered before, and I will look into it.

My wife is the original owner of 79 TA with rear disc brakes as it had the original brakes on it.

When driving it a while back, I noticed that the brakes were not stopping as well as they had been, and the parking brake was not keeping the vehicle from moving on a slight grade.

I pulled both calipers, and they looked like they were frozen.

The pads looked like they had never been worn at all.

I replaced the rear calipers and pads but still have the same problem.

I bled the entire brake system.

With the vehicle up on jack stands, I applied the parking brakes and could still turn the rear wheels.

I checked the spring on the calipers.

They were completely compressed.

With the TA up on jack stands, I placed the rear wheels in motion with the engine on.

I tried to panic and stop the wheels; all it did was slow down them.

With the engine off, I had the brake pedal depressed fully, and then I rotated the rear wheels with a little effort.

I checked the front wheels, but I could not rotate them.

The master cylinder was replaced a few years ago.

The proportioning valve was replaced last year.

Is there some special way to place the lever on the brake caliper?

I appreciate any help you can provide.
 

jenniferny

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I hope that I remember this right!

The rear calipers are side-specific.

While my car was under warranty in 1980, the dealer replaced the right rear caliper with the caliper from the left side.

When you do this, the system can not adjust the rear brakes, and you will never have a good brake pedal.

The internal adjusters turn in opposite directions when you apply the parking brake.

What happens is that the caliper will constantly try to loosen the rear brake adjustment.