i have a 241c 272 t-case in my burbon. i have a 4l80e tranny. i want a 205 t-case but,... how and what do i need to swap the t-case and have everything work? i have 4:88's and also want to know how i should gear the t-case?



i have a:
1991 V2500 Suburban with 5.7, 4:88's, 4" suspension lift, 35" bfg's, no cat, 4l80e, 14 bolt rear, 10 bolt front

 

This might help.

http://www.atlas-tc.com/pdf/50/50-0410.pdf

 

1971-1979..? does this apply to 1991 also?

 

That is the year range of the transfer case. It likely would work with later NP205 GM transfer cases as well seeing as how they really did not change much of anything. But from 85-91, GM offered a long spline input for the NP205 which would not require a different input shaft to the NP205.

If you can find a 1991 NP205 transfer case, it would be optimal as it will already have the provisions for the VSS that you need.

If you already have a 4wd 4L80E, it may be a bit different in terms of output shaft length. Most kits center around having the long spline 2wd shaft. Here is a list of all of the output shafts offered for the 4L80E:
170F Output Shaft - 7-3/8" - Short Spline - w/ O-Ring .................................................. 1 91-96 34980 8661595
170F Output Shaft - 7-5/8" - Long Spline - w/o O-Ring ................................................ 1 91-96 34980A 8661596
170F Output Shaft - 8-1/2" - Short Spline - w/ O-Ring .................................................. 1 91-96 34980B 8661597
170F Output Shaft - 4-3/8" - Short Spline - w/o O-Ring ................................................ 1 91-96 34980C 8661598

While very rare, the 1991 V3500 (I think crewcabs and 'burbs) were the only GM model offered with an optional 4L80E/NP205 combo.