Rumble from transfer case

[Jspafford]

A few years back I swapped in a manual transfer case. I got it from a local PnP and have had zero issues with it's performance.

Last winter in Ohio we had a pretty nasty February and I used 4WD a lot. I leave my hubs locked all winter. When running 4WD at close to highway speeds I get a nasty vibration and rumble that is not constant, but will go away a second, then come back. If I shift back into 2WD it will go away.

Weird thing is, if I run hubs locked 2WD I don't hear it. If I run 4WD with the hubs unlocked I don't hear it, it is only when I have the hubs locked and in 4WD.

This is my DD and I am afraid to run it too much with this noise. Winter is fast approaching. It is loud enough that I know it is not good to continue like it is, and I am afraid of a catastrophic failure on the highway.

The only other thing worth noting is back in 2006 I was hit and had to replace the front pumpkin, but I reused my old gears and just changed out the axle beam. This shouldn't affect it, but thought I would throw it out there.

Thanks!

 

[alwaysFlOoReD]

I don't know if this will have any bearing on your problem, just throwing it in the mix. Years back I added an extra shim to my 9" to get poorman's posi. I got a humming vibration [comes and goes on a regular cycle] after that. I found out I should have marked the [?orientation of the ?] ring gear [tooth] to the pinion [tooth]. Maybe something to think about, anyways,
Good luck,

Richard

 

[strvger]

front driveshaft bent or balance issue?
u joints all good?

either one or both could have been affected in that accident. just a thought.

 

[Jspafford]

U-joints in both axleshafts are new. Well, not new, but they were replaced after the accident. Everything was, ball joints, tie rods, u-joints, steering box, etc.

I just find it odd that with any combination of the driveline spinning it doesn't do it, but it only does it when the front driveline is actually recieving power.

I've also noticed the front end kinda hunches up (for lack of better explanation) when in 4WD and taking off. Almost like it gets power first or something.

I dunno!

 

[4x4junkie]

Have you checked the fluid in the t-case and the front diff to see if it's dirty and/or metallic-looking at all?

 

[Jspafford]

Have you checked the fluid in the t-case and the front diff to see if it's dirty and/or metallic-looking at all?

T-case Check, front diff, not since replacing it. I will check it soon!