Half Shaft Diameter

txsc

Registered User
Do all SC's have larger half-shaft diameters on the RH side. Or, is this determined by transmission type, production year(s), or other criteria?

Thanks,

JD
 
Yes they all have the larger shaft on the right side.
No, they don't. I can't remember the specifics, but I'm sure it is listed somewhere here. I think only the early 5 speed models had the bigger diameter "fat shaft".
 
My 94 5-speed has the fat shaft, my sons 90 automatic had the fat shaft, and i have the entire rea end from an 89 manual that has it.
 
I know the rule is that only the manual cars received the "fat shaft", but I've parted out five 89-90 autos that had the "fat shaft" on the right side.
 
I think that just about every car recieved a fat shaft from the factory. if a car has the small shaft it may be a replacement for a worn out shaft.
 
All manual transmission SC's...89 - 95 came from the factory with one fat shaft. Early model 89 - 93 automatic SC's I'm not sure about but I am sure 94 and 95 automatic SC's did not come with a fatshaft halfshaft.
 
That's interesting Rod. Maybe 90 was the cutoff for autos having fat shafts? I know my 92 did not come with one. I haven't checked all of them, but I'm pretty sure all of my 5 speeds have them (two 89s, one 90 and on 95)
 
Well, just finished pulling the differential and half shafts out of my parts car; it's an 89 5-speed, so it obviously has the fat RH shaft. All the 5-speed stuff is going into my son's 90 automatic car.

I'll have him crawl under his car tomorrow, and see what it has. If it has the fat shaft, we'll use his since his car has lower miles. Otherwise, I have the one from the parts car to use. I'll let you know what I find tomorrow.

Cheers,

JD
 
Well, just finished pulling the differential and half shafts out of my parts car; it's an 89 5-speed, so it obviously has the fat RH shaft. All the 5-speed stuff is going into my son's 90 automatic car.

Hey Jerry. I would definitely go with the large shaft for the RH side. The prevailing thought is its supposed to break up some harmonics in the drivetrain. Im guessing due to the lack of a torque converter and the gear ratio difference. There is some shock relief from the clutch springs, but be sure your trans mount and engine mounts are in good condition. They tend to take more of a pounding.. at least with the way I drive they do..:D
 
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We checked my son's 90 automatic today, and it has skinny shafts on both sides. So, we've already started detailing the 89 manual "fat shaft", so it's ready to go in with the rest of the swap. We're going to put this thing together just like as if it were a factory 5-speed car.

The motor mounts were replaced not too many miles ago at the dealership according to the receipts I got with the car. They also installed a new oil pan, so the originals must have been completely shot. I'll double-check the transmission mount before I pull his car apart for the swap, but the last time I looked, it was in good shape. If it's questionable, I'll order a new one.

I'm sure this one will take a bit of a pounding too! He doesn't drive it hard, but he WILL be learing to drive a manual transmission the moment it comes off the jack stands! Sink or swim, son; Haha... I've had him out in mine a few times for familiarization, and he's a natural. But, we never left the neighborhood with it (no license tags). The true learning will come in the day-to-day traffic environment. In all seriousness, I'll be taking him out for several driving lessons and practice before I turn him loose on the world. I want to make sure he's ready. But like I said, from what he showed me driving my car, he will come up the learning curve quickly.

JD
 
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