I am having trouble with my 79 rx.
After bleeding the brakes, they work great for about a week. Then, they start screeching and grinding. If I am at idle speed (5-10 mph) they really grab and grind. If I push the brake pedal firm, I don't have that problem. Also, sometimes the first time I push the brake pedal I don't have great pressure. That is usally when they grab and grind. If I pump the brake pedal I do get better pressure. It may only require one or two pumps to get better pressure. I don't really know what to do.
Please help.

Scott

 

I have an '80 and it does the exact same thing. I am going to get new pads and see if that helps at all. If not, then I have no idea what the problem is.

 

i have a 85 GSL-SE that had a similar problem,it was my brakepads squeeking agenst the calapers! to see if your problem is the same,spray WD-40 between the two (NOT THE ROTOR!!!!!!!!!!!) if it stops, there is a spray to put on them for a more long term solution.

 

You have drums on the back which are out of allignment. Pumping the brake pedal brings them closer which gives them better pressure since they are so far away. Most likely your shoes are shot, or your star adjuster assembly is frozen.

The grinding most likely is bad, tell us where the grinding is coming from front/back so we can get a better idea.

 

The grinding feels like it is coming from the front pads and rotors.