91 Bravadas and Syclones are 27 spline, and are shorter. Typhoons, 92-97 Bravada and Astro, and 97-only Jimmy and Blazer AWD are 32 spline, and longer output shaft. Other than the output shaft, extension housing, and rear seal, the other parts are identical, and interchangeable.
There is a recent thread on T-case differences, and how to check them. There are probably at least a 100 Threads on here about this.
but beware that Viscious clutches DO go bad, and there are bearings and bushings that have service lifes as well. The chains and planetary are fairly durable, but occasionally have issues. Particularly high-mileage units from astro vans (heavy).
Service parts including bearings, seals, a chain and a V-clutch are about $550.00 from
cobratransmission The case can be overhauled by a DIY'r without any special tools. Just a triip to the machind shop to use the press to do the output shaft and V-clutch.
DaveP
