40-45mph hopping

kino_fab

kino_fab

KTPA Tech Official
Joined
Aug 19, 2007
Messages
2,244
My truck and also a few friends of mine with similar trucks (ex cab long bed 4x4, 5spd) are having a puzzling delima with all of our trucks having a slight bouncing or hopping between 40-45 mph. We have all tried everything we know of to fix it but getting no where. One of them even went through the extent of replacing all the u-joints front to back, new tires, carrier bearing, track bar, wheel u-joints and tie rods with no luck. Any idea's?
 
My truck also does this around 40 mph and is the same thing(QCLB 4x4 5 sp.) I am trying to figure it out also.
 
rearend bouncey feeling....

i get it off the line no matter how much throttle input, and slowing down.

replaced rear u-joint on axle end... went away for about an hour then came back... 2 piece rear shaft = junk.

trying to find one for a newer truck to chop splice and make work for me... hoping 5" aluminum
 
Hmmm. I know steel wheels arent really all that true. Tire shops can check for vertical/horizontal run out either way. It'd suck to drop a bunch of money on that driveshaft when my 99' has a 2 piece that works fine.
 
i have 16" afro market aluminum wheels on mine.

Best way i describe it- its like having 38" or bigger mud tired out of round. just a hoping up and down. It changes its amount of hop too. sometimes its pretty smooth, other times i cant keep my hand on my center console.

Does it an any gear, gas, no gas, etc.

gets worse as the fuel tank empties also.






'
 
I'm wondering if this had anything to do with my tranny locking up on me the other day (5spd). The shifter moves around alot all the time as if something is bad out of balance.
 
mines always jiggled around. When i did my clutch i put in a new tranny mount. now when i let out the clutch in 1st the whole shifter moves several inches
 
I take it this is a 4 wheel thing? My dully has no problem. But when I bought it IT needed new u joints so I had it balanced at same time 165.00
 
My 2000 ext. Cab LB does the same thing, BUT it didn't do it until I put new wheels and tires on it. I just contributed it to the tires being a little out of balance.

Rick
 
My 97 ex cab dually does the same****!!!! If I didnt have somuch in the engine build and new trans I would trade it!!!!!!! I have changed all the above also,even wheels and tires and balanced drive line.
 
seems to be a extended cab longbed 4wd issue.... hmmm


is everybodys at the same speed? mine vibrates at about 70-75 also, hit 80 and she smooths out.
 
Ditch Baby said:
seems to be a extended cab longbed 4wd issue.... hmmm


is everybodys at the same speed? mine vibrates at about 70-75 also, hit 80 and she smooths out.
Click to expand...

Yep pretty much exactly the same. I didn't notice the hopping until I swapped in the 5 speed and the dld t-case. I need to rebuild my dhd and throw it on there to see if it's in the t-case. I can't think of anything else, everything is brand new on this thing.
 
check your wheel bearings in front wheels,,, fixing one right now in a 2001 cummins, it started do do this so called "hop"..... this one is completely done for
 
my truck had a little bounce between 40 and 50 mph. for me it turned out to be a transmission mount was broke, i replaced that, and doesnt seem to bounce anymore. just another thing to check.
 
Me and my brother have the same problem. QCSB though one being a 6 spd and the other an auto. I thought it was the tires.
 
You must log in or register to reply here.
Back
Top