So I have read many posts bout this same issue of the rear end bouncing/ hopping/bucking while accelerating but none have have said the problem only happens sometimes. One day Ill head to work and the back end is just bouncing away bad then 10 hours later when I go home it will be as smooth as buttern BUT it always bounces when I brake hard. My u joints are shot and will be replaced this week but I couldnt see that causing it. I intially though wel maybe the shocks are worn out but why would this only happen sometimes? I can be driving down the road doing 80 and its smooth then all a sudden it will start bouncing a bit then go away a minute later. Has new calipers on front, drums on rear and new lines around and My brake pedal used to have to be pumped before driving it but now its fine. Could this be a rear wheel cyl or brakes need to be bled properly?

 

A high possibility the rear EMG brake hardware has come apart on one side
and jambs while running, from vibration etc.
The parts have no place to get out unless the backing plate gets bent to let some fall out.
Good luck.

 

my e brake is not hooked up. The bracket that holds the cable tight rotted and so the cable just hangs with some slack. Should I be looking into it or maybe just weld in a new bracket?

 

My parking brake pads just failed me. They fell out of place and like bluegrass said they have nowhere to go. Mine came out and got wedged in between the rotor. Mine was causing grinding noise and really bad vibration. Only made noise and vibrated on certain occasions. Took tire off then rotor and let the parking brake pad fall out. Problem fixed. Hope this helps.

 

parking brake pads were already removed when i pulled the drum off. when I jacked the truck up off the ground before i removed the tire I gave it a wiggle and the axle assembly moves in and out about an 1/8 of an inch? Is that right? I replaced the shocks and no better. I am having a bad front brake system problem right now all a sudden so I wonder if that could be a culprit.

 

The axle movement is normal.
They are held into the carrier by 'C' clips in a groove.
Only way you can get the axles out is to remove the spider gears in the rear so the axle will push inward to expose the C clips for removal.
Good luck.

 

Does your truck have rear disc brakes or drum? My 2000 warped the rear rotors easily and when they warped the rear would jump up and down when I braked. I noticed it the most when I stopped slowly just before stopping.

Ok, i just read your post about drum brakes but the principal still applies is the axle twist happens when braking.

 

I hear ya and thanks for the reply but it only does it sometimes. My front brakes are not releasing and I notice its hopping more so I am wondering if theres a constellation there.

 

Mines been doing it recently as well. It is the road because it only does it on a certain area on my way too and from work. But it never did it before. For now, I suspect the rear shocks and leafs are shot. They have been squeaking for some time now. And the leafs are original and have done some work in their 14 years on the road. I get pretty bouncy hops at about 20-35mph through that certain area but don't notice it any other time.
I'll be changing the shocks soon. Hopefully that is it.