Front Auto Hubs???

[Plasnart]

Autohubs locking is based on axle shafts relative movement in relation to the hubs. So, hub still and axle moving will cause it to lock (as intended, by the way). If the TC oil happens to be too thick, it could transfer some movement to the front driveshaft even disengaged. Little movement, no torque whatsoever, but enough to have the axles engage the autohub. Happened in my GQ and I recall seeing it explained here somewhere.

Hence the auto trans fluid specification for the TC which confused me greatly until I think it was @mudnut who explained it, then it all made sense!

[BrazilianY60]

Hence the auto trans fluid specification for the TC which confused me greatly until I think it was @mudnut who explained it, then it all made sense!

Well, ATF is not the only recommended oil for the TC, by Nissan's standards. I interpret this recommendation like this:
If you have an AUTO, then use ATF on the TC just in case seals fail between the AT and the TC, no harm is done.
If you have a MANUAL, then use the GL4 stuff the same as the MT, so if seals fail, again, no harm is done.

If the GL4 stuff (90w75, etc) is too thick for your location temperatures, then it may cause this that we are talking about. Just change to a thinner oil on the list (as long as it is GL4) and retry.

[mudnut]

Well, ATF is not the only recommended oil for the TC, by Nissan's standards. I interpret this recommendation like this:
If you have an AUTO, then use ATF on the TC just in case seals fail between the AT and the TC, no harm is done.
If you have a MANUAL, then use the GL4 stuff the same as the MT, so if seals fail, again, no harm is done.

If the GL4 stuff (90w75, etc) is too thick for your location temperatures, then it may cause this that we are talking about. Just change to a thinner oil on the list (as long as it is GL4) and retry.

My '94 manual GQ Transfer Case is listed to use ATF.

I had issues with crunching into gear when cold in a partially rebuilt gearbox. The mechanic that had fitted it for me, had added 5GL oil and his advice was to add a bit of ATF that will help with smooth cold changes. But being a new member of this forum, at the time, the advice from a member, to drain the gearbox oil and refill it with GL4 made all the difference. Another older mechanic had also suggested adding a bit of ATF as well. From this I have come to the conclusion that gearbox oil diluted ATF isn't so bad. But on saying that, there are numerous brass components in the Nissan manual boxes that might eventually be eroded by ATF.

[Plasnart]

…….But on saying that, there are numerous brass components in the Nissan manual boxes that might eventually be eroded by ATF.

And also GL5 apparently. That’s why it’s so important to stick with the lubes specified for your particular model.