Groan while backing up

[DUNE RCR]

So my truck just started this new annoying trend. While I am backing up I will get a rather annoying groan if I have the wheel turned. It doesn't do it while the wheel is straight but as I turn the wheel it will do it and gets worse the further/ closer I get to the bump stops. It doesn't do it while going forward just reverse. I also backed up with the wheel straight then turned the wheel about half way (both ways) and held it, to rule out the steering rack, and it groaned like I was rubbing a tire, but none of my tires rub. Any ideas at this point will help as I want to avoid breaking anything.

 

[rickybobby]

Perhaps check you CV joints

 

[obie]

Are you sure none of your tires rub? I had the same problem with my F150, and thought it was my CVs too. I asked a friend of mine to watch carefully as I backed up with the wheels turned and he did see the front right tire rub. Maybe have a friend double check before you replace CVs or take it to a shop. I'm guessing you have a Torsion Twist?

 

[DUNE RCR]

My rims have a 2.5" backspace and have plenty of space between the back of the tire and anything it could possibly hit. If it were my cv's (which are fairly new, I rebuilt the entire front end roughly a year ago) wouldn't they do it while going forward too? I was wondering if it could be something like the viscous coupling in the transfer case getting ready to go, or possibly one of my diffs acting up. Also all fluid levels are good too. That's something I check almost weekly.

 

[DUNE RCR]

Also something to note...its more of a feel then a sound. The sound it makes is more of a resonation throughout the truck. Kinda like when a tire rubs a sway bar, just an example.

 

[DUNE RCR]

Are you sure none of your tires rub? I had the same problem with my F150, and thought it was my CVs too. I asked a friend of mine to watch carefully as I backed up with the wheels turned and he did see the front right tire rub. Maybe have a friend double check before you replace CVs or take it to a shop. I'm guessing you have a Torsion Twist?

Yes I have the torsion twist, lift shackles and body lift, but nothing rubs.

 

[DUNE RCR]

Anybody have any insight on what I may have wrong here?

 

[thorney_5]

Did you ever figure this out? I'm having a very similar issue.

 

[DUNE RCR]

Sorry I'm a bit late on this one....
I am starting to believe the viscous coupling inside the transfer case is binding up. I did a drain and refill twice within one week with no change, just progressively cleaner fluid. Both CV shafts were replaced under warranty and I dropped the diff and opened it to see if there was anything wrong inside.

This is why I am led to believe the viscous coupling is binding/locking up.
Guess I'm going to start looking into doing the TC swap. When I get around to swapping everything over to the 4406 I will update the outcome of the 4404.

 

[thorney_5]

How old are your wheel bearings/hubs? That's what mine turned out to be. Certainly less expensive than a TC.

 

[DUNE RCR]

Roughly a year old. I have a lifetime warranty on almost everything I have replaced and change them out if I have any uncertainty about it.