Hades12

I picked up an Automatic 85 Gs a few weeks ago, It did not have a drive shaft. I picked up a shaft from an 83Gs auto. The one from the 83 is to long by about 2-5 inches. I thought they would be the same. Have I missed something, Or are they suposted to be different?


Also I now need one for an 85 GS.


Hades.

Glazedham42

iTrader: (4)

Pretty sure of what happened here. Your 85 GS Automatic is probably a 4 spd overdrive tranny like mine. The 83 that you got the driveshaft off of is probably a 3 spd automatic, which isn't as large of a tranny as the 4 spd overdrive. In other words, there is more room between the tranny and the diff on a 3 spd auto then there is on your 4spd 85 GS. So to make up for the differences the 83 GS uses a longer driveshaft. Your 85 GS has a larger tranny so as a result the driveshaft is shorter. This is more than likely your problem.

Jamie

Hades12

Sounds Like a good reason.

BUT

I went back and found that The penion is smaller than the penion end of the Drive shaft. Measured the penion and found that it is about 3 1/2 inches across at the bolt holes. Measured an 85 LSD I have and it is about 4 1/4 across, So I may have an 82 or before rear.

Would an 81 82, Shaft from a 4 speed trans work? anyone have one they want to sell?

Rx7carl

Theres your answer. When they added the electric OD they had to make the shaft shorter, meaning that the standard trans shaft no longer fit.

Rx7carl

Look in the FAQ thread and look on Felix's site. He has all the interchange info there. But my quick answer is nope. You need the correct tranny or get the later driveshaft and change the pinion flange also. Sorry for the bad news.

bouis

It's a shame I don't still have the auto driveshaft from my '85. If you want to ditch the auto tranny, I'd be happy to share my experience. I'm sure that Glazed would too.

680RWHP12A

the only drive shaft that will work for your car is one from the same year 84-85!!! only ...no other driveshaft will work...

Hades12

Could I get the Early Shaft and have it cut down to length? I assume that the Trans end is the same on all the years?

Thanks for the Help

bouis

I don't see why not.

Hades12

I may change the Diff Penion and then have my shaft shortened. How hard/what needs done - to change the Diff penion?