The Stovebolt Site Forums The Shop Area Driveline SM420 to NV4500 swap

I'm beginning the process of swapping my SM420 for a NV4500 tranny in my '65 C20. I'm looking for any advice and/or pictures from someone who has done this. One problem that I see is that I need to relocate the crossmember that is right behind the transmission and it has the parking brake linkage attached to it. ANy advice would be appreciated.

Richard

How is the swap coming along? I too am interested in replacing my SM420 with the NV4500 in my '47 1ton panel. I think the original brake lever was bolted to the side of the transmission. The SM420 came out of a dump truck, and the brake lever is bolted to the side, but it goes to a drum mounted on the rear of the transmission. The crossmember that was behind the transmission is no longer in the truck with no problems for 10 years. I'll want a transfer case on my NV4500, so I don't know if there will be room for a brake lever, I may have to add a foot pedal.

the GM nv4500 had two different bolt patterns for the bell housing mount and two different bearing retainer diameters. the earlier 4500 (95 and earlier) had the smaller bolt pattern and smaller retainer. High Impact gear has some good info and are pretty knowledgable with these transmissions.

http://www.high-impact.net/transmission_and_gear/nv4500.htm

You should be pretty happy with one of these trannys in your truck, they add to the driveability and give the truck a whole different feel!