4WD transmission questions

[unklian]

On  the GM 4WD transmissions,
is there any sort of differential front to rear ?
How does that work ?

Any of the ones I've seen,offset the drive to the right.Is it possible to install the tail housing upside down to offset the output to the left ?

And did they make 4WD Powerglides ?



Thanks in advance for any help.

[Crosley.In.AZ]

Depends on the year of the GM vehicle... late model stuff the front drive shaft is on the drivers side ( left)

[enjenjo]

On  the GM 4WD transmissions,
is there any sort of differential front to rear ?

Yes, most full time 4x4 have a differential in the transfer case, so do the some of the part time cases you can shift on the fly. There are others wit a viscose coupling in place of the differential. Some of them have a lock out feature in the third diff too.

How does that work ?

Pretty good Actually the trans drives the differential case, the rear shaft is connected to one side gear, and the front shaft connects to the other, usually with a chain. The newer stuff may be set up differently, but that's what the older ones had.

Any of the ones I've seen,offset the drive to the right.Is it possible to install the tail housing upside down to offset the output to the left ?

It would be left and up. Actually, for many years, Ford set the front shaft to the left. but outside of the Dana 20 transfer case, I don't think there are any other Ford transfers that will fit a GM trans. And a Dana 20 is not real strong.

And did they make 4WD Powerglides ?

The only ones I have seen were for racing, and everything was custom made.  But there is a way to do it easily with factory parts. Before 1978, on most pickups, Ford used a divorced transfer case, it was mounted on the frame with a third driveshaft coming from the trans. If you used a shorty Glide, with a short driveshaft, and a divorced transfer from a Ford, it would all hook up



Thanks in advance for any help.

[unklian]

With the Ford transfer case,
if the rear drive shaft was removed,will it still drive the front wheels ?

Or does the power go to the axle with the least traction,like an open differential ?

[enjenjo]

Yes it will. That is a straight part time case, you are either locked in, or locked out. A buddy drove one for over a year on just the front axle.

[unklian]

The divorced Ford box looks like a workable solution.Thanks.

[Crosley.In.AZ]

I had a 1974 GMC 4x4 pickup for sale.. I took the guy out in the dirt a few miles from the house.  I pitched the rear drive shaft out ( broke front U-joint).  I took the rear shaft out and drove home on the front diff.

he bought the truck.  

[Ed ke6bnl]

Yes it will. That is a straight part time case, you are either locked in, or locked out. A buddy drove one for over a year on just the front axle.

I purchased a dually rear end from a guy the took the rear end out of the 1ton dually dropped the rear fame made it a flat bed to drive vehicles on the rear behind the cab and use the front drive shaft to drive the vehicle.

[RodZZilla]

On  the GM 4WD transmissions,
is there any sort of differential front to rear ?
How does that work ?

Any of the ones I've seen,offset the drive to the right.Is it possible to install the tail housing upside down to offset the output to the left ?

And did they make 4WD Powerglides ?



Thanks in advance for any help.

No factory Powerglides.  It is becoming the Hot Ticket in the rockcrawiling world.  There have been a few adapted the last few yrs.  GM trucks up to 1987 and Blazers, Suburbans, and Crew Cabs up to 1991 had passenger side drop on the transfer case.  Full time cases (NP 203) Have a differential.  It can be overridden with the LOCK position.   Part time cases (NP 205, NP 208, and NP 241) do not have differentials.  There can be oiling issues on them if you invert them.  The 241 is available in pass and drivers side drops.