Rear end jumps

[84CUCV]

My friends K5 has stock 10b and 35" tiers. Out of no where it started to jump when he got on or off the gas, what could that be?? I have no clue.

thx Mike

 

[txfiremank5]

What do you mean by "it started to jump"? Is the rear axle housing rotating upward when he gets on the gas?

 

[primr87]

if its got 4" blocks in the rear he may have bad axle wrap causing the u-joint to bind

 

[84CUCV]

2" block. This is how he put it to me. When he hits it or lets off the whole truck just jumps. I dont know how else to put it. I do see what you mean about the block. I see how that could do it, but would it do that with just 2"?? When i see him i will get a better description. Mike

 

[primr87]

try watching the rear pinion while he pulls back and forth so you can get an idea of whats happening. mine used to bind when i got on the brakes to hard

 

[CHEVY 4WD]

Check and make sure the u-bolts are good and tight... I dont really think the bock is causing a problem... Im running a 4in block ( ) and a locker right now but i still dont have any problems with wheel hop or anything(I do have AT's which dont grab that hard offroad but ive done quite a few stand still burnouts and I dont get anythere either)

 

[BIG STEVE]

Check out the rear mount under the transfer case it lets the rear jump up puting the drive shafts upper ujoint in one hell of a bind thats what happend to mine any way when i went to gmc to get one they had 15 in stock
that means they sell alot of them put a jack under it it hard to see if its bad just looking at it.

90 jimmy
02 gmc HD

 

[84CUCV]

Cool thanks guys i will give it a try. Mike