ZF6 Manual Transmission 4x4 F250 Power Stroke

Glad it wasn't something expensive!

So as a driver of a manual 5 speed, I would say more or less normal!

I needed to back into the last two spots up hill with our 11,000# 5er. Reverse is geared higher than granny low and 2nd gear on a manual.
I can't maneuver while rolling at idle in reverse, requires a little slippage of the clutch. That would be the first issue a little chatter, that can shake a lot of things, mine is a little worse as I have a DD clutch. The other would likely be a little axle wrap. Put in low range and unlock the hubs. I can't yet do that with my Ram, getting a 2 Low kit very soon.

Thanks to all that responded to my question of my ZF6 4x4 F250 6 speed
and the problem I had backing up hill with a 12,000 5th wheel. It's the nature of the beast to develop "axle wrap" the fix could be torsion bars at a quoted price of 1400.00 or simply going into 4 wheel drive and easing into the site. It all makes sense, and the next time I encounter the problem I'll try it.

Just curious, OP, did you ever figure this out?

Did your truck do this before the clutch work? It sounds like it may be "axle wrap", where the rear leaf springs twist around due to the torque loads on the driveline. You used to see what we called "traction bars" on the old muscle cars for this very reason. Especially with a new or stiff clutch, there's not a lot of slip in the driveline to take up the uneven torque, so the springs twist and cause the truck to hop, jar, and rattle. Auto transmissions tend not to do this as bad since they are operated by moving fluid instead of a direct mechanical link with little "give". This is especially noticeable when the truck is in a gear that is too high or when the load is heavy. Here is a short video to explain it better than I can:

Axle Wrap

Like Ductape suggested, shifting the transfer case into low range really helps, since the Z6 is geared a little high in reverse, in my opinion. Just be careful not to "romp" the pedal unless the hubs are locked in though, as low range really puts a LOT of torque on the rear driveshaft and differential if the front isn't engaged to share the load.

Hope this helps!
Regan

Moved from Forum Technical Support

ZF makes great trans.
I don't know what the noise is but I do know that if it's making a lot of noise you don't want to drive it that way. It will just get more expensive.

I had one of those; definitely not normal. Do you use low range to ease the strain when reversing into a spot?

You need to get to a shop. Someone needs to get into it and see where the noise is from. Probably not the clutch if it's only in reverse.