my dad was driving his 99 f150 (220,000 kms on the clock) and he said it seemed like the brakes locked up on the rear passanger, now the snow is melting today, salt, sand, slush, i dunno if it just froze the brakes when he was in the store or what, so he drove it home we took both rear wheels off and everything seems to be fine, except rear driver seal leak (we were gonna check the diff fluid but coudlnt get the plug out), there was a little noise, i think from warped rotors, then the abs light came on when we were running it on the jack. we put it back together and took it for a spin, its not clunking, whinning, or locking up anymore....we are confused

oh yea and the abs light went off......

 

Is it real cold in your area? It's possible the brakes were hot and melted snow which then froze when he was in the store.

As for the plug in the diff, give it some penetrating oil and some heat. Not a lot of heat, just get the plug good and warm. Sometimes I will put a wrench on it and lightly tap the plug with a hammer. Not whacking it.

 

its above freezing but alot of slop on the roads, yea we are gonna try some heat on it when we get it into the shop

 

If the brakes stick again you may want to pull them and inspect the rubber boots covering the pistons. I've seen a few pistons rust a bit and then stick.

 

good idea