4x4 conversion

[FormerMember]

Originally Posted by jhcolli

Got a 69 GMC 1/2 ton I would like to convert to a 4x4. I've found it difficult to find what I'm looking for on the forums to see if it has already been discussed and I'm sure it has many times.

1. Will 73-87 GM truck front and rear differentials bolt in to my 69 GMC without modification?
2. Are there other differential alternatives available that would not require me to cut or lengthen the tubes?

I'm going to a big swap meet next month so I'd like to look for the conversion parts there. I plan on picking up an NP205 TC but don't know what my options are for differentials.

3. I have a 700R4 trans and I know about the output shaft conversion kit. Will I have to modify my floor pan to fit the TC? My original trans was a three on the tree. I know there were high and low hump pans.

Thanks

1: The front axle will, the rear will not, unless it's a later model 1 ton rear. They changed the rear spring pad spacing. Of course, you could cut off the spring pads and weld 'em on.

2: Ford axles will fit, if you want to swap in a Chevy input shaft to a Ford t-case and run that (driver's side front drop). Dodge does too (passenger side drop), but the front spring pad spacing is wider, by an inch overall. Some just kick the springs out and run 'em.

3: Nope.