Hello,

I'm chasing down my dreaded 70 MPH vibration on my 2004.5 long-bed quad-cab automatic Ram 2500. The vibration disappears when I remove my front driveshaft. I'd like to borrow a known good working/non-vibrating front driveshaft from someone in the Golden CO area to swap in and perform a test drive.

Here is what I've done so far:
1.) Rebuilt NV273 T-case (ALL input/output bearing races had spun in the cases. I glued them back in with loctite bearing and seal retainer, no radial play anymore); all new bearings and seals throughout.
2.) Rebuilt front driveshaft with Spicer XL non-greaseable joints (by a shop) - quality joints. The cardon joint is not brand-new, but was replaced 20k ago with a new unit and still feels good.
3.) Had two different driveline shops (both very reputable) check phasing, straightness, run-out, and balance FOUR different times (3x at one shop and 1x at the other)... read, the shaft should be good, both thought the cardon joint was in fine shape so no need to replace... or so I'm thinking...

As a side note; I replaced my rear two-piece driveshaft with a single-piece aluminum unit. When the recently balanced/checked front driveshaft is removed the truck is smooth as silk, no vibes. When I put it back in the mirror vibrates so bad I can't see the cars behind me.

I'd like to swap in a known good front shaft and try it before spending any more $$ on new/rebuilt shafts, etc. Anyone have a line on a spare front shaft to borrow? Please advise.

Eric in Golden CO.

 

I'd just find a shop to balance/check your driveshaft...

 

http://www.yellowpages.com/golden-co...haft-balancing

 

Do you have history with this truck or was it acquired with this vibration? Front end collision damage?

I had a theft recovery bought at auction come into the shop with a ton of drivetrain work done at many different shops with no change at all. Same deal as yours......remove the front shaft and all was good.

We ended up rebuilding the front differential with a know good ring and pinion set (A set from my own truck) as the gear pattern looked horrible. Problem was solved!

Seemed kind of strange, but we had no history and had to try something.....

 

That's a good point...

 

I don't think it's the driveshaft either. First it's rebuilt and balanced you said.
Second, unless you're running it in 4wd, there is no power going through it, it's just free spinning and it would have to be pretty wore out to feel it if there's no power going through it.
Considering the t case bearings are new too, I'd look at the front diff.
It may not vibrate with the ds out because the pinion has no substantial centrifugal load on it compared to spinning the ds around. Look for any slop in the yolk coming out of the diff.
Borrowing a driveshaft would tell u the same thing and is a good place to start if you can find one. I'm too far away or you could take mine. It'd be nice to have someone remove it for me so i can grease it easily again!

 

Eric, you have certainly put alot of work into trying to solve your vibration problem. I am concerned that since the bearings in the transfer case spun in their housings that even though you put new bearings in and locked them in, that they are no longer seated in perfect radial alignment to each other. I do not know how MUCH play was made up with the loctite, but the very act of spinning bearings in the casing/race means that there is likely more then a few thousandsth of an inch, which means they COULD easily be out of axial alignment due to having spun and worn the case in the first place. The fact that you have rebuilt AND balanced the front DS and the problem persists seems to indicate that I may be right. Be sure to post back what you find out.