Does the front dif turn when the transfercase is in 2 wheel drive? I have tried a search but I haven't found an answer.

Thanks,

BoiseRob

The front shafts are splined to the wheel hubs, so they both rotate. AFAIK, there's a disengage in the diff and the transfer case. That replaces hub locks (manual or automatic) and means that the front diff gears and the front drive shaft do not turn in 2wd, are engaged in 4wd.

This always amazes me considering the effort and cost manufactures place on mpg. I'd love to have a set of manual hubs on my truck to disengage them, save a bit of mpg and wear/tear on CVs etc...

I am guessing its this way to combat past issues associated with automatic hubs, most folk want true "on the fly" engagement, and 1500 autotrack models requiring instantaneous engagement when in "auto" mode (which, by the way, I love for my wifes Yukon....no more telling her when to engage/dissengage 4x4).

wait a minute, I just re-read Idle-Chatters response. Doesnt the drive shaft spin all the time too?

wait a minute, I just re-read Idle-Chatters response. Doesnt the drive shaft spin all the time too?

Nope it doesn't. The front diff has a solenoid that engauges when the t-case is engauged.