Shaking problem

[1979C20]

Okay then, when I was dropping my drive shaft, I found a 3rd part to my issue. My center support bearing(carrier bearing) was messed up. The rubber bushing seperated from the bearing. So my best bet is my tranny mount started this all, the ujoint went out because of the extreme angle, and the center support bearing bushing ripped because of the angle the driveline was going through it. So, my "friends" down at checker helped.me oit. We got the carrier bearing off and a new one on, replaced the ujoint, and I picked up a tranny mount. The best part is, it was all free!! I had life time warranties on all of it since I had already replaced them all before. The bad news is, when I tried to get my tranny mount out, the bolt just kept spinning inside.of the rubber of the mount. So I got a hack saw and started to cut the bolt, then the blade broke. Well, I was replacing everthing in the checker parking lot because I haf no way to pull the parts off,l and brong them in because my truck is my only transportation. So I had to leave the tranny mount for tonight. I have to pick up my girlfriend from work and checker was closing. Ill probably swap the new one in tonight some time.

[87454westernhauler]

Glad u got it fugured out! exspecially for free!! lol!

[bake74]

My u joint is shot, gonna swap it out today. And my tranny mount is screwed

     Well that will certainly do it.  I hope after fixing those it solves the problem.  Keep us informed.

[1979C20]

Well, im stumped. Brand new u-joint. Brand new carrier bearing. Brand new transmission mount. Everything is in line and tight. Motor mounts are good. But, my truck is still shaking between 35 and 25. Its not quite as bad, but its atill very promineny. Its driving me nuts. I can fell a strong vibration in the steering wheel, and the cab is shaking. Any more ideas?

[bd]

Are your u-joints in time?

[1979C20]

Yes. My 2 piece drive line has a flat spine. Theres only one way it goes on. And all of the drive shaft weights are still on.

[bd]

If you set the vehicle up on secure jacks and removed the wheels (reverse the lug nuts to hold the drums on), do you suppose you would still have the vibration?

[1979C20]

I was thinking about doing this. Putting the rear axle on jack stands and then accelerating to just above 35, then slowing down to see if it still shakes  that would narrow down the problem.area to the front of the truck if it doesnt shake. I just dont know how safe it is to have my truck on jack stands at that speed.

[bake74]

      Put several jack stands around the back.  I have done this but 1 set I used had chains on it to strap to frame/axle.  I was going to suggest front rotors or tires, but this way you can eliminate the rear end.

[thirsty]

Sounds like what people call the death wobble in four wheels drives the way you are describing it.
Don't you have newer wheels and larger tires on your truck? I would pull the wheels and check the lug holes to make sure that they aren't worn. Check the tires again for a broken belt. Go over all steering and suspension components closely.

I bought a K20 once that had the death wobble. On the test drive the guys tells me to power thru it and it will come out of it. I couldn't do it the first time...it was that bad, I had to pull over. Then I got it past the death wobble and it drove fine. I ended up buying it and replacing the stabilizer shock and a tie rod end. Never had a problem again. It had 33"s on it and the tires would do their own thing left to right until they really got rolling fast.

Maybe you have the same type of thing starting with yours even though it is 2wd.

[Jason S]

Death wobble is not limited to straight axle trucks.

A long time ago, a company I worked for had a worn out 85 2 wd dually flatbed truck that had death wobble issues.  Everything was stock, just worn out.

Recently I saw a 90's F250 4x4 (Twin traction beam front end) begin the death wobble on the road...  Interesting to see from the outside...

[bd]

Recently I saw a 90's F250 4x4 (Twin traction beam front end) begin the death wobble on the road...  Interesting to see from the outside...

Isn't it?  Really excessive caster can cause a shimmy too....  But, worn parts are probably the biggest offenders and oversize tires with aggressive open tread exaggerate the issue.

[1979C20]

I was told that ball jpints may be the culprit. Im going to check it all out tonight. Thanks guys.

[1979C20]

Okay, well I have gotten 6 suggestion that its ball joints. I didnt get a chance to check them yet, but im prepared to have to replace them. I have a set of coil sprin boosters that I want to install if I do have to replace them im going to do the uppers and lowers, replace my swaybar bushings, and going to install the upper ball joint UNDER the control arms so I have a little more suspension travel between the upper control arms and the crossmember. Im thinking about replacing my tie rod bushings as well. Just to freshen up the whole front end.