[85raiderburban]

Youll find these gears common in 14B full floater equipped C20 trucks that have 454/TH400 combo. I run 33's (295/75/16) 3.21 gear out back. Ive got factory 31's up front. I have a toggle switch shift 4L80 that makes the 454 turn 2K at 68 mph. I am able to hold gears longer to get up and going from a dead stop.

Factory 265/75/16 - 1st to 2nd 10mph, 2nd to 3rd 22mph,3rd to 4th 35mph
295/75/16 - 1st to 2nd 15mph, 2nd to 3rd 26mph, 3rd to 4th 40 mph.

I guess you could say she performs more like a 700r4 with 31s. But all in all, its all about your engine combo. If that diesel packs enough TORQUE, it will move these 3.21s with ease. I actually broke traction in this truck before with the Gen V 502/TH400 combo it had when i bought it.