Thumping sound from torque tube/tranny

[Aufenbahn]

Got a strange sound today. Driving home from work everything normal - suddenly a sound I haven't heard before. A thumping sound seems to be from the rear and corresponds to rpm. In other words if I shifted down it thumped faster. Also only made the sound when accelerating or decellerating and the more I give it gas the louder it is. Needless to say I drove the next mile or so home a bit slower.

I'm wondering if its possible for the bolts on the coupler between the torque tube and the tranny input shaft to be loosening, backing out and hitting the housing. But then it seems like it would be a constant noise.


Anybody have any ideas, similar experiences?

Thanks

[q5ka]

When my ring and pinion was going out, I had a similar issue.

[Razorback1980]

When is the last time you changed your clutch? Could also be torque tube bearings or the bolts you described. The noise won't be constant as the lower the gear, the higher the rpms, the more thumping. Since it's rpm related, I don't think it's the ring and pinion. That should be speed related.

[Aufenbahn]

I guess what I meant by not constant is that the noise goes away when you hold a steady speed. And also after I heard it I sped up and slowed down a couple more times to listen to it and then it stopped making the noise. Is there a cover under the area by the front of the tranny where you can open up and look at that coupler between the torque tube shaft and the tranny shaft? I guess I'll have to get out my manual.

[Aufenbahn]

I just checked on Clark's and it appears that I can take of a cover on the underside of the tranny bellhousing and check things out so I guess that's my next step.

[Aufenbahn]

Well I took the rubber plugs out and everything looks like its allright and tight so I'm still puzzled. I guess I'll have to drive it more and see if I can figure out what it is.

[harryrick]

if you "swerve" left to right does the sound change?

if you push in the clutch does the sound change?

[svandamme]

check your axle bolts...
can produce that rpm related sound, and have it go away at steady speeds, to come back doing transition from coasting to load, to decelleration

easiest thing to check (feel axles near wheel)
cheapest thing to fix (retorque the (new) bolts&threadlocker)