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Chevy G20/30 van driveline question

I recently bought a 1980 Chevy Van which believe is a G30. Its either a 3/4 or 1 ton. It has a 350 and a T400 transmission. It has a 2 piece driveline, and it had dropped the rear section of the driveline before I bought it. I had a 1991 Chevy G20 with a 700r4 for parts that I planned on using the driveline out of, however I didnt realize the transmissions were different until I got home. The 1991 also only has a 1 piece driveline, so it is very different from the 1980.



I managed to find what I believe is a 70s Chevy Van, I think it has a T350 but it might have a T400. It does have the 2 piece driveline though. In the event that it does have a T350, will the rear section of the driveline still fit?



The 1980 Van also has an 8 lug full floating axle, while the 70s van is a 1/2 ton and only has a 5 lug. Will the U-joint still fit?



Thanks

It sounds like the hanger bearing for that two part drive shaft crapped out. Why not replace the original hanger bearing?

Tester

It most likely did and will be replaced if so, (I havent looked over everything yet), but I need to find a driveline to get it to move first.

So are you saying that the slip yoke in the hanger bearing pounded out the U-joint at the differential, and now the the differential is all messed up?

Tester

No, the van has a 2 piece driveline. Theres the transmission, 1st driveline section, (hanger bearing), 2nd driveline section, then differential/rear axle. The 2nd driveline section (what connects the 1st driveline section and the rear axle) is what fell off. The splines off the 1st section are good, as is the u joint yoke off the axle. Im wondering if I can take the 2nd section off another van if it has a TH350 instead of a TH400, since I think the trannys are different lengths, and Im not sure if Chevy made the 1st or 2nd driveline section shorter/longer to compensate for the tranny lengths.

You’ll have to take some measurements. As long as they’re the same length, same yoke size/spline count, and as long as the u-joints are the same, it will work. I have my doubts about the half ton driveshaft mating to the heavy full floating (usually dana 60) axle. The only way to tell is to try it, as I never have and don’t know for sure if it will work.