Z31 driveshaft and other driveline compatability information

Hahaha using an aluminum shaft guarantees you'll never have to rebuild your u-joints
not sure how you came to that conclusion considering the amount of cars that have aluminum shafts that are serviced- but you'd definitely have to rebuild them less. especially if they're oversized for the application.

The spicer 1310's or whatever that are on the new shaft are definitely nice pieces- but I'm pretty sure the ones on mine are non-greasable. Opt for greasable joints if you can. Depending on how much power you put down and what kind of launch you subject the drivetrain to, you can twist an aluminum driveshaft into a pretzel off the line with good traction if your u-joint has the slightest amount of resistance in its rotation.

And as careless said, greaseable reduces strength so careful which route you go down
lolwut? i didnt say that. any resistance from a worn out or poorly maintained joint will cause bind.
greaseble joints will allow you to make sure that doesn't happen for a car that sees a lot of use. the itty bitty fraction of a percent that the grease fitting takes away from the strength of the unit is negligible. the strongest u-joints are the solid spicer XL ones, but I'd rather have grease fittings for this climate we live in.

also, there are plenty of cars running alu driveshafts without issues. If it's built beefy enough and engineered properly- there will be no egging of the holes. if anything would egg the holes or break it into pieces, it's launching a 600-700 whp car from a stand-still on some grippy tires. most aftermarket aluminum driveshaft companies will guarantee their 3.5 inch driveshafts to at least 600whp.

as for flanges- speak to whomever is building your driveshaft. you need to find the bolt circle diameter (NOT the shape of the flange body itself). for the later models where the 4 bolts measured from center to centre make up the shape of a square- you will find that it's something like 2.25" inches. For the earlier models where the bolt pattern is rectangular, I have no idea. It's something like 2.25" x 1.95" but you should just measure whatever your current driveshaft or current differential companion flange has. Or better yet just cut it off your current driveshaft and send it to them if you dont need it.

In addition, the joints are not the same size in the N/A and turbo (at least manual) shafts; turbos are bigger so you cannot simply swap yokes or diff flanges on the shaft. On a side note I have only seen replacement-type joints listed for the turbo driveshaft's joint sizes, not the NA.

The turbo and NA uses the same u joint. I rebuilt a driveshaft from a 88 2+2 which took the turbo u joint. It's currently running perfectly.

Did you press out the old U-joints or grind them out? BTW: what does grinding them out mean?

Grinding is taking a dremel cut-off wheel and removing the stakes that hold the bearing cups. http://z31performance.com/showthread…ford-Driveline

I believe Augustus Maximus used a shop press to press his out.