Help with vibration after 30 mph.

[taxreliever]

92 xlt, 4wd, aod, 351w, auto(for now) hubs

So from 0-30 mph, the thing drives like a cadillac, but just after that, the rig starts to shimmy or vibrate. It's a constant vibration and gets a little stronger once I get up to speeds 50 or so, but then it's the same from 50-75.

ALSO, I feel absolutely nothing on the steering wheel at any speeds and the entire front end had been inspected and is tight, meaning, ball joints, tie rods, and all are good to go.

The guy that installed my remote starter has some knowledge in mechanics and says that all of the drive shaft components look brand new and have recently been replaced and may be unbalanced, but not sure....

Anyways, thought it wouldn't hurt to see what you fellas thought or if you had anything specific I should tell my mechanic if I bring it to him.

FRONT FRONT:

FRONT BACK:

REAR FRONT:

REAR REAR:

 

[smokey]

Sounds like a wheel tire problem.
The drive shaft looks ok by the pics

 

[LEB Ben]

I agree with Randy...sounds like it may be a balance problem with the tires. However, if the dshaft components have recently been touched, possible they didn't put them back in sequence.

 

[greystreak92]

Check suspension mounts as well. Front shocks, axle pivot bushings, radius arm bushings. I chased a vibration that only reared its ugly head between about 40-60 MPH but it was a nasty thing that ended up being a cracked axle pivot bracket on the inboard side of the passenger half of the front axle. Not saying yours is anything thing severe but the closest thing to a rigid mount that the TTB axle halves have are the axle pivot mounts.

 

[m78]

Also test for rear drums being warped, by using the parking break. Hold the release and press the parking brake steadily. If you get a pulsing , your drums could be warped. It's more noticeable after they have warmed up some usually.

 

[taxreliever]

Thanks fellas.....more issues and wanted your expertise:

The guy that did my remote start checked my transfer case fluid (we noticed a small leak) and couldn't feel anything so he put a quart of fluid in there and I took it out tonight with the whole family and there was zero vibration from speeds beyond 30 mph and a slight vibration at around 30 mph.

First question: could low to no fluid in the transfer case cause my vibration from earlier?

Why did it stop at 30+?

How big a job is changing the seal?

 

[taxreliever]

Scheduled to take it in to get diagnosed this wed, but wanted to see what you fellas thought first?

 

[taxreliever]

And going to have him check all your suggestions above.

 

[DNFXDLI]

Put a good sized screwdriver or prybar between the u-joint and yolk and check for play..while in neutral with no parking brake on.

 

[taxreliever]

Damnit!

So, my mechanic said the shaft was rebuilt wrong....the po put all brand new u-joints on both ends of the shaft, and had the shaft rebuilt but the end closest to the tcase wasn't done correctly causing a half inch bounce.

So, now I have to get a new shaft and will be left with all new u-joints....oh well, as long as it's done right, I don't mind spending the bucks....bronco graveyard has them for $250 plus a core charge.

Need to know what my transmission is first and am not sure.

Also, would I be able to resell those u-joints? I don't run my rigs hard, so my new ones should last the life of the vehicle and won't need any back up ones.

 

[flareside_thunder]

Take a pic of your trans pan. I don't see why you can't reuse those joints.....what's the deal with that? Transfer cases are easy to split and reassemble, what seal is leaking?

 

[taxreliever]

Take a pic of your trans pan. I don't see why you can't reuse those joints.....what's the deal with that? Transfer cases are easy to split and reassemble, what seal is leaking?

Apparently, they don't just sell the shafts, which is what was bad. If I could, I would just replace the shaft and reuse the new ujoints. I can't even find an option online for buying just the shaft.

The other option is taking the shaft to a machine shop and having him fix it there, but costs would almost equal just buying a new one with all new joints and everything for $275 with shipping and Broncograveyard doesn't even charge a core charge like everyone else. They're also on ebay for $300 with no core charge of course.

I've read about guys just replacing ujoints and parts of ujoints, so I'm not sure why I wouldn't be able to just buy the shaft, but maybe I can just sell the ujoints, which are also selling on ebay for good money.

 

[taxreliever]

Finally got the Bronco back.....new shaft installed and working great!

Tcase cover removed for a new seal and everything inside looked like it came from the factory new, says the mechanic. SWEET!

And new tps.

 

[fatherdoug]

Good deal! Did the new dshaft solve the vibration problem, and what transmission did you end up with in the Bronco?

 

[taxreliever]

Good deal! Did the new dshaft solve the vibration problem, and what transmission did you end up with in the Bronco?

Works awesome now!

I have the E4OD.