6 spd trans

[00 black ram]

I was wondering how much the 6 spd will take. Do you need to replace input shafts and etc.... I don't know much about the trans and any help would be nice.

 

[Redline Ram]

some of the early 6 speeds had a small input shaft i believe but the later ones already have a bigger input shaft. i have seen several break the output shaft (mainshaft) running 500-600 hp.

 

[Ph4tty]

That 2000 nv5600 has a 1 1/4 input while the HO trucks from '01-'02 have a 1 3/8

 

[BCSCUMMINS]

If your motor is a 235hp the 6 speed has a 1 ¼ input shaft, if it is a 245hp motor it has a 1 3/8 shaft. As far as how much power they will hold, I don’t know. It all depends on your transmission, a lot of people brake stuff with a stock HP truck and some make 6-700hp on them with no problems.

 

[00 black ram]

I have heard alot of guys say that they won't last if you pull or put in a DD clutch. I won't be pulling the truck, maybe some drag racing, but mostly keeping the strokes and maxes in check around home

 

[Phily 911]

I'd say if your modding a Cummins it's one of the best trannys, in stock form to do it on. But it's not the best for Drag racing.

 

[JFlagg]

Its definitely not a dragracing trans, but as manuals go I'd say its the best out there coming from the factory....I have a DD in mine with 436rwhp and I wouldn't have a problem putting 600-700hp through it. Mine is a 2002, so 1 3/8" shaft...