brake lockup
 

when i apply the brakes more than once at low speed the right rear brake locks up what is causing it to do that? is it adjusted too tight?

Wheel cylinder leak? Brake fluid on your shoes will cause the pad to "grab".

Like gr8scott51 said, either Brake fluid or the self adjustor is not working correctly. Every time you touch the pedal it could be tightening the brake. I had one do this once when doing about 65...shew what a ride!

i just pulled the drum and everything is clean and dry. it only locks up if i apply the brakes more than once at low speed less than 10 mph. at faster speeds i can brake hard and it dosen't lock up.

fixed it it was just adjusted way too tight

Just to toss another cause out there... Mine used to lock up one rear wheel after the brakes got heated up from driving and never when cold. I found the cause was a stuck emergency brake cable.

It was making the brake stay on just a little bit. This made the brake heat up and get sensative.

A warped brake drum can cause lockup at low speed as well...Especially when wet.