I have a problem with my 4x4 F150. The rear breaks (drums) tend to lock-up when you brake suddenly, and then the abs works, but it only locks-up one of the rear wheels, either the left or the right. This is very dangerous, because when I´m driving in the city and have to make an emergency stop, one of the rear wheels is going to lock-up, and even with the abs, it is scary.
I´ve tried replacing the drums and replacing the shoes but the problem persists. This problem is not normal, because even with the bed loaded, the problem is still there. I´m even considering on buying a disk kit for the rear end.
Do you have any idea how to fix this?

I Hope someone alredy fixed this on his f150 and can help me,

Regards

JTGE

 

sounds like one of your wheel cylinders is sticking. also might want to put a new spring kit in also.every time i put new rear shoes on i spend the extra 15-20$ to put a new sprimg kit in.another thing flush all your old fluid out. old fluid can cause problems like this.

 

X2 springs, and fluid flush

might not hurt to have the drums "turned" or "cut"

 

Could also be that was is adjusted tighter than the other. Maybe self adjuster on the one is not working.

 

those self adjusters never seem to work right.i usually adjust the rears every oil change. take some high temp grease to those threads that helps a little.make sure you put plenty of grease where the pad contacts the backing plate. thats often overlooked.

 

When mine starts doing that, I get some 120 grit sandpaper and knock the glaze off the shoes. Also wash the dust off with water. It helps my truck for a few thousand miles.

 

Thanks for the help. I´ll try the new springs and I´ll also change the cilynders.

 

When i had the same problem i thought it was my new GM Brake booster but asking my father, he told me that i only have to change the cyclinders...