overdrive trans

[amerigraf]

I currently own a 1984 Chevrolet C30 Silverado truck factory equipped with the 454 carbureted gas engine and four speed transmission with a non-synchronized "granny" low gear. The truck was converted by the Oleynik Body Co. in Detroit when new for use as a car hauler with a 20 ft. enclosed box. I am trying to determine which, if any, later model 5 speed overdrive manual transmission could be installed with minimal modifications. I am particularly concerned with overall transmission length, mount location, shifter location, and input and output spline compatibility with the clutch disc and driveshaft yoke currently in the truck. Does anyone know from what year and model truck i could find a compatible trans? Please don't suggest an aftermarket overdrive unit as the $3000 cost is over my budget at this time. Thanks.........Pete

[Colorado Kid]

I believe an NV 4500 from a 1993 or later GM would be a simple swap. The NV4500 is longer, but shortening driveshafts is pretty cheap, it's making them longer that gets spendy. Be aware that there is a Dodge version of the NV4500 that will NOT bolt up. GM's still putting NV4500s in 2500HD and 3500 trucks (with the 6.0L engine). From 93 to 2000 they used it in 2500 and 3500 trucks with all three engines (350, 454, 6.5TD). A 2WD version is relatively rare, but they do exist out there.

 

I haven't done this swap, but I know that it has been done.