67mustang302

You need enough yoke sticking out so that when the suspension compresses and the yoke slides in, the radius of the yoke doesn't bottom on the seal. You have way too much yoke sticking out in that photo, and it will put excessive load on the output shaft bearing in the transmission.

Spicer makes great u-joints, if the shaft has a 1310 end, then just get a 1310-1330 crossover joint. Preferably the Spicer Life series, non greasable and sealed (the Life series have crazy good seals on them). Alternatively you can have the shaft fitted with a 1330 end.

azdriveshaft

These guys have given you the best answers to your question but let me put it all together for you. With the driveshaft installed and total weight of the car on the tires there should be 1" on the slip yoke showing out of the back. If the driveshaft is to short it can cause extra wear on the bushing inside of the transmission and wear out your slip yoke as well. You will also want to have your driveshaft balanced after it has been shortened/lengthened or even changing slip yokes can create a vibration and led to bearing wear. As for your new yoke you can use a conversion U-Joint to convert it from 1310 to 1330 but the correct way to achieve your goal is to replace the front weld yoke with a 1330 yoke and use a spicier solid 1330 U-Joint.

One more tip, your grease-able 1310 U-Joint is installed backwards. The grease zerk fitting should be installed toward the weld yoke or you will not be able to fit your grease gun onto the zerk for proper greasing

I hope this helps!

CyprusMustang

Thanks guys, it's 1am here and I'm itching to go outside and check something. I didn't know there was a 1310 1330 crossover u joint. That said, I want to measure the total length of the new slip yoke that I have. I think with that installed, it might reduce the 1 1/2 inch gap I have now and not have to take the driveshaft back to lengthen it.

What you guys think?

Is this it ??

http://www.drivetrainamerica.com/p-5...-13101330.aspx

CyprusMustang

I figured out the problem, when car is on the car lift, the gap is smaller than when the car is resting on the suspension. Is that how it's supposed to be?

69mach1377

Yes, it is how your car is driven.

CyprusMustang

Everyone is saying the opposite that when the car is on a lift, the length should be greater. I found the opposite. Anyway, driveshaft is at the machine shop again to add an inch.

azdriveshaft

The travel of the suspension changes with every vehicle, 4 link rear ends will get shorter when lifted, leaf spring cars depend on which side the shackle is located ( front or rear) none of that matters in this case. its all about where the slip yoke sits while the car is at ride height.

CyprusMustang

Your right and I wish I knew that before I meaasured the car on the lift. I assumed it was longer so I took that into consideration when measuring. I also measured with a yoke for a 1330 U joint whereas mine are 1310. Anyway to make a long story short I dropped the car to ride height and squeezed my way and measured 2.08 inches of gap with the driveshaft bolted to the rearend. So off to the machine shop to add 1.08"

azdriveshaft

Sounds like you should be in good shape now bud! Let me know if there is anything in the future I can help with.

69mach1377

The way I measured for mine was front tires on ramps, rear axle on jack stands. Gave me room slide around underneath, safely. I also made sure the car was level same as when on all fours.