NV3500 never came from the factory behind a 5.9. They did behind a 5.2, and rumor has it, the bellhousing bolt pattern is very close. On bolt (at the very top) doesn't line up, I think.

That said, if the trans really was behind a 5.9..... I wouldn't expect it to last very long.

 

Two years on a nv3500 with 40x15.50r20 tires , 4.10 gears and a 5.9.

 

Hey Merc! Long time no see!

Welcome back.

 

Are the 6 bolts for the pressure plate the same on a 5.9 flywheel as the 3.9? what clutch and flywheel combo do I need to order to run my 3500 behind my 5.9l?

 

You need a flywheel for the 5.9, it is externally balanced, the other motors are internally balanced, and are NOT interchangeable. Get a new clutch and p-plate for the 5.9 as well, trans spline count didn't change with engine side. That way, you can be sure everything fits.

 

I have the NV3500 behind a Chevrolet 350. The truck has over 400K miles on it and unknown previous history. Motor replaced and rear end rebuilt .... no idea on the transmission but it works great.

 

Some 2500s came factory with 5.9 and nv3500

 

Erm, no, they didn't..... Maybe the light duty 2500s, which were basically a slightly beefed up 1500..... but in all my years here, I haven't seen one.