Well i looked but i couldnt a solution for my problem. My brakes make a thud when i hit them a little harder as i role to stop. But this only occurs in 4wd. Its Like Boom and the brakes go into death grip mode or something. Because after they catch its a nice jerk and loud thud which is easily felt. I just dont get why this happens in 4wd. I have a 97 F150. Any help is appreciated.

 

sounds like a possible master cylinder problem?? when they grab real bad like that. check all your caliper bolts and all your lines as well.

 

you might check your fluid level and try see if there is any air in you lines... just a thought but i don't really know for sure. good luck

 

does the pedal get soft then goes back to normal?? if it does that id say bad master cylinder.not sure about the 4wd connection though.we had a 99 e150 van at work that pedal would go soft not quite to the floor but then would grab almost throwing me thru the windshield.was a bad master cylinder

 

It's probably the right rear drum shoes sticking, and the whole system locks up when in 4WD. Does it when it's cold and damp, but then tends to go away when it's driven for several miles?

 

I have a question about brake drums on a 98 f150. I am going to replace them but really don't if it is worth taking it to some one to replace them of if i should do them myself?