Suppose someone with a 1500 and 318 (cough) wanted a six speed, mainly for a wider gear spread and faster acceleration, not so much for pulling). However, the output shaft on my engine is too small for the input shaft on the NV5600. Any advice?

 

Lots and lots of JB Weld? You can use that $hit for everything.

Kidding. Unfortunately I have nothing constructive to add

I am interested in how this plays out, however.

 

Well, for starters, you'd have to make room for it. It's much larger and heavier than the 3500 so custom brackets, beefed up frame rails, larger clutch, bearings, etc. Then you'd have to lift the body probably to fit it under it. Also, there's really not much benefit to getting it for the extra gear as first is total granny at 5.63 versus 4.01 in the 5spd. 5th gear is 1:1 as 4th is in the 3500. If you want to check out more info, click here: http://dodgeram.org/tech/specs/Ramspecs.htm

If you really want to get tighter shifts and more gears get a GearVendor overdrive unit. You'd have a 10spd then.

 

The six speed swap is not a good idea. There are no benefits only thing it will do is make your truck slower and heavier.

 

Do you have the tranny yet? If not, have you priced one out yet? BIG BUCKS.

A friend of mine is putting one in his older diesel, but it will not bolt up either. He's having a friend at the local machine shop make an adapter of some sort.

I agree, I don't think it is worth the effort (or the mega bucks) for what you gain (basically a granny gear and a much stronger tranny).