I am able to get a cheap NP203 transfer case with 4.10 reduction out of a 73 Ram. I want to know if it would work. Here is what I know so far.
it is isn't side drop. To fix this I would just rotate it to a driver side drop.

It looks like it uses the same speedo gear so it will work until I put my factory 01 wiring in, then it will read off the rear diff.

Is the bolt pattern for the case the same? What about the splines?

 

I don't think you can rotate it that far, and still get adequate lubrication.... I don't even know if the input shaft is the same......

 

Thats the problem I'm running into is the input shaft. I only want it for the 4.10s plus the guy only wants $50 I could have returned my Atlas

 

Something doesn't compute here. Back in the day the NP203 had a 2:1 low range, and I'm not aware of any lower gearing conversions. Doubling it with a NP205 results in ~4:1 but then the drop doesn't matter as only the reduction box is used. What am I missing ?

 

T cases from back then where full time 4WD also.
As said low is 2:1
https://www.dieselhub.com/drivetrain/np203.html

 

I verified the box does have a 4.10 gears no reduction box.

 

That's the factory ratio as that's what is stamped on the tag.

 

So... how do you fit 4:1 ratio to a NP203? There simply is no room for bigger gears. At the early 2k there was a LoMax gears available for the NP205, and that was with the custom case. Stock casing just didn't have enough material to make room for the lower gear set.

 

Borrowed this picture of the stock NP203 range box from the CK5.com site:




https://ck5.com/forums/resources/ord...nsfer-case.72/

There's a shift collar for hi/lo range inside the case. Under that is low range gears on the countershaft. Low range consists of gears set of four. Biggest gear mounts to a intermediate shaft, which is not pictured, and is almost a size of that hole. In order to get 4:1 gears it would have to be much, much bigger. And as it can be seen, just impossible to fit in there.

 

I don't have the case a guy is selling it. I thought I could save some money by returning my Atlas because i really don't want 2 4wd levers in the truck. Not to familiar with the power wagons other than some engine and suspension work