Transmission Swap

[weldingrod]

Are the 1984  720 2 wheel drive and 4 wheel drive transmissions interchangeable?

[bottomwatcher]

Which way are you going? 4wd does not have speedometer hole.

[datzenmike]

They can be interchangeable. There are long 31.5" and shorty 26" so length must match or get the driveshaft with it and probably the longer or shorter console . 4x4 gear sets are wide ratio while 2wd are mostly mid ratio but this may not be a concern for you unless rock crawling. 4X4s drive the speedometer from the transfer case so if putting a 2wd box in, find some way to seal the speedometer pinion sleeve.

 

Always replace the rear seal when ever a transmission is out. It's only $3 and 2 min to do and a lot easier than in 3 months when it begins to drip on the driveway.

 

GL4 80w90 is the factoy recommendation but I've had good luck with the GM Delco Friction Modified Synchromesh Transmission Oil. Shifts are smoother, faster, so much easier when cold, and I can now down shift where I couldn't before. It a semi synthetic oil, very light weight and slippery used in the later Corvette and Camaro. Lordco has it, about $37 CDN for 2 liters.

[weldingrod]

Thanks Mike, always learn something new here. Going to have a 2wheel drive shortly for demolition, will post years etc. in Classifieds when it arrives.