Rear diff fixed, now what?

[Nanoose]

After months the rear diff has been repaired - Yay!

I've driven around for a few days and initially I was struck by how much quieter everything was and that I was now hearing more from the front end than from the rear. Was out earlier though and the front end noise reached epic proportions. The noise itself is like a howl, at first I thought I was hearing the tires. It's not a grinding noise.

The noise changes in relation to wheel speed, not engine speed. It makes no difference if it's in two or 4 wheel or if the truck is in gear (it happens while coasting too). The one thing I did notice was that the noise stops when I give it some gas..as long as I'm accelerating (or keeping torque applied), the noise doesn't occur.

I'm stumped. Thoughts?

Thanks!

Dave

[Partsman]

Got lock out hubs on that thing? If not, could be your front diff.

[I Leak Oil]

It could be the front diff but the fact that it happens in 2wd (no power load on the front drive train) may lead you to looking at the rear drive shaft or gear boxes. Usually diffs make noises on the drive side or coast side when on or off the gas but that's when they're actually getting power. Try removing the front and rear drive shafts, in turn of course, and see if anything changes. Try removing the front drive flanges to see if that changes anything. Or...perhaps that's just the sounds your rover makes....

[jonnyc]

I'd start back at the hubs comment. If lock-out hubs, make sure they're unlocked.

[Nanoose]

oh that would be tragic if it was the front diff...I'm in denial at the moment...retorquing u-bolts now... *sigh*

[Partsman]

I'd start back at the hubs comment. If lock-out hubs, make sure they're unlocked.

Which is why I mentioned it, if they are engaged, then everything spins all the way back to the transmission, if they're disengaged, then in two wheel drive, nothing spins in the front.

[Nanoose]

Spent yesterday and today lubing, tightening and greasing anything in sight. Took the landy out for a test drive and about 2 miles from home I heard a "clunk" then things started feeling funny. I quickly pulled over, looked underneath and realized the drive shaft had partially popped out of the rear diff. I unbolted it and the flange came off as well. I think that when it was reassembled the cotter pin wasn't put in the castellated nut and it just spun off. I think it being so loose would explain most of what has been happening...at least I hope so!

[I Leak Oil]

With any luck that's it and no other damage has occurred. Drive train noises are tough to diagnose from the drivers seat, nevermind over the internet. I've found that if you think you hear or feel it in a particular area there is a 50/50 chance it root cause is elsewhere. Never rule anything out until it's ruled out....

[Partsman]

With any luck that's it and no other damage has occurred. Drive train noises are tough to diagnose from the drivers seat, nevermind over the internet. I've found that if you think you hear or feel it in a particular area there is a 50/50 chance it root cause is elsewhere. Never rule anything out until it's ruled out....

Yup, you got that right, on the wife's car, we heard a noise that we could have both sworn came from the front passenger side wheel, turned out to be the rear spider gear....not even close to where we thought we could hear it.