I am looking at buying another highboy with an automatic C6 and it is fulltime 4X4. I dont know much about the fulltime 4X4. How do they compare to the non fulltime 4X4? It has a different transfercase right? Are they as strong? Any info would be appreciated.

Thanks

 

If its fulltime 4x4 its got the NP203 Full-Time T-case. There strong but there down fall is that it is chain driven. If you can lift the front side with a jack, engage t-case to Loc-Low or Loc-High, go back to the tire thats off the ground and try to turn it...if it has lots of play (turns 1/4 of of the tire size clock-wise or counter clock-wise) the chain might be to replaced. Other then that its a nice thing not having to get out and lock those hubs on part-time cases.

 

its great i like them and they are hard to find

 

My 75' has a 203 fulltime case. I was planning on switching it to a part time unit until I ran it for a while in the winter. The 203 works great on slick roads in the winter but does not have the binding when making tight turns associated with running in 4wd. When you get in a hard bind only one tire will spin(front or rear)but you can put it in "lock" and then you will get power to the front and rear at all times. I plow snow with the 203 and it works very well since there is alot of maneuvering involved.

One way to explain how the 203 works is to compare it to a differential. It puts power to the front and rear like a differential puts power to the left and right tire but when in a bind as where only one tire(left or right)will spin the 203 will only put power to the front or rear when in a bind. You can shift into the "lock" position and then the transfer case is locked in like putting a locker or spool in the differential.

I think they quit using the full time type transfer cases because most people only need 4wd about 1% or less of the time and the part time cases are a little more efficient in the fuel mileage department. If you use 4wd a quite a bit I think the 203 is the way to go. I wish my 96' had one.

 

That's great info Crumm, thanks. I have an extra 205, how hard would it be to replace the 203 with the 205?

 

It's my understanding that it is nearly a direct bolt-in installation...if you have the yoke (front and rear). Of course you may need to correct the driveshaft lengths.

The Ford NP205 transfer case uses the 6 bolt circular bolt pattern . It has a left hand drop (driver's side). It is supplied with a 31 spline female input.

Rear Output
Is a 32 spline shaft and will accept a 1310, 1330, or 1350 u-joint yoke, and the 1310 CV yoke.

Front Output
Is customarily a 32 spline shaft, same as the rear with interchangeable yokes.


The Ford NP203 has a 31 spline female input. The bolt pattern is the Ford rotation of the 6 bolt circular bolt pattern

 

Yep the divorced 205 is a direct bolt in replacement for the divorced 203 except for the drive line length.

 

So I would have to get the proper length driveshaft and wouldnt I have to replace the front hubs with the manual locking type?

 

Yes, you'd have to put locking hubs on.
There is no differential built into the internal gears of the 205 - it's designed so that the differences in the rotational speed of the tires is taken up by the "give" of the surface you're driving on.
If you left your full time hubs on, then you'd be turning the driveshaft into the transfer case via the front diff. I don't know if the 205 would be happy with that in 2wd.
In any case, as mentioned, you'll loose gas mileage making all those metal bits spin!

Also, when you're doing the check mentioned by FordBronco69, look at the UJ's on the front driveshaft when you try to turn the wheel to make sure that you don't have any play in them otherwise you might think the chain is stretched.