Hello All -

Hoping I can get pointed in the right direction. I have a 1999 Ram 1500 4x4 Club Cab SLT Laramie w/5.9. I have an intermittent vibration that is coming from the drivetrain somewhere. I noticed it a couple of months ago, but haven't really drove the truck much. Heres what happens:

AT 45-50 mph, after the transmission has locked up, I will sometimes get a vibration or shutter in the drivetrain. It seems to happen more often when the truck is under load, such as going up a hill or accelerating. It also seems to happen more when the truck is cold. If I lift off the gas, it disappears. If I shut the O/D off (and the rpms stay up), it doesn't appear. It only happens after the O/D has engaged, and the T/C has locked up. (Obviously the engine is turning pretty low RPM) I replaced the axle bearings, brake shoes, seals. I inspected the carrier bearings and pinion bearings, and they seem to be good. If I put it up on jackstands and run it at 45-50, the rear axle appears to be pretty quiet. I inspected the U-joints, and they appear to be ok (nothing loose). The only thing that appeared to be odd was that I shook on the driveshaft up at the transmission end, and it appeared to have a lot of play. I also noticed a small amount of grease had dripped out of the back seal.

I originally thought it was a axle bearing going out, but now I think it may be coming from the transmission or transfer case?? I've never had a transfer case off of a new Ram, so I am not familiar with any bearings that may commonly go out, or how difficult this may be to fix. Any ideas/suggestions???

Thanks in advance,

--Mark

 

Hmmm - 31 reads and no response...

Well, I think I have narrowed it down to the transfer case - pulled it off and its on its way to Zumbrota Bearing and Gear for a rebuild. If this doesn't solve it, its likely the transmission itself. [>:] I thinks its going to go down the road....

 

Maybe a warped driveshaft/U-joint?

Sounds a lot like what happens to people who get a big lift but don't drop the transfer case. Certain mph = vibration which stems from the driveshaft 9 times out of 10. If your U joints are worn, the same vibe can happen.

Just a guess, though.

 

Interesting B12Tueton, my thoughts exactly. I have bad ujoints and she shakes like an underpaid stripper waiting on promotion. At first i thought it might be a bad alignment, but after some searching on forums and youtube, it has been equivocally narrowed down to the ujoints! Thanks for the confirmation!

 

Have you fixed the plenum? The slight shudder you're feeling when in OD is a symptom of a small misfire in the engine due to a vacuum leak around that crappy stock plenum plate...this misfire results in a small shudder or shake in the truck and is often attributed to a suspension or drivetrain issue when in reality it is an engine issue. For whatever reason, OD magnifies the misfire causing a shudder felt inside the cab of the truck. There won't be a check engine light either, atleast not at first. Just a thought, you may still be correct in thinking it's related to the transfer case or transmission.

 

^This is true.

 

agreed davies

 

This is a TEN year old thread....... Why are we resurrecting this?