Ive had trouble with brakes on this truck for a couple years...started to get hopping after getting the GM 1 ton wheel cylinders...changed out the shoes....recently changed master cylinder...front rotors, and pads...i used to have the whole truck shake...now after the rorots it only shakes in the rear....i checked the wheel bearings in the rear..greased them and tightened everythign...everythign looked good!...ABS/brake light has been on for a year......the hopping occurs much more during braking when coming off higher speeds....as well as during braking during the final 50 feet of braking...its a hopping in the rear...i tried backing the shoes off a dozen turns on each side to make them really loose and it still does it....more noticeable after truck is hot then in the mornings...pedal travel is consistent ...no leaks...i triple checked...i haven't lost a spit worth of fluid

help guys...

 

springs in the rear might be worn out and causing the rear to hop when braking. just taking a stab at it

 

hi
how old are the rear shocks and bushings ?

 

rear shocks/bushings/leafs are all factory...drums do have some minor discoloration in some spots from the previous heat abuse....im gonna try and get them turned...hope that fixes it....i"m hoping that others have had the rear hopping during braking and cured it...its like a shaking/hopping...like a jackhammer effect...its almost like abs just more pronounced...but it can;'t be abs since the system is shut down because the light is on

 

My rear end hopped badly after getting new tires when the tire guys disregarded my request and way overfilled the rear tires. They had them at 80psi, I wanted 55.

 

question. does the abs light mean the system is shutdown/disabled completely or that there is a problem(malfunction.
Clark

 

my rear brakes do the same thing, depending on brake pedal pressure.
im chalking it up to the rear drums being old and most likely out of round.

 

hmmm come to think of it i got brand new and bigger tires at the time as well...it would be nice if that was it (darts to check the tire pressure )
well what do ya know...one tire was at 80psi cold and the other 78 psi cold....im gonna go for a spin later this eveing keep u guys posted....the only other thing would be drums

 

turned out to be drums out of round...had them turned...smooth brakign from all speeds now....let's hope it stays this way...now I just gotta wait for the lights to go out in a month or so