Driveshaft pics XR T9, XR C3, Scorpio A4LD, Scorpio T9

[merkurdriver]

First and foremost make sure the shaft you are putting in the car is still balanced.

Here's a good article on the driveshaft angle.
http://www.angelfire.com/pa3/lyzcoinc/alignshaft.html

The stock shaft with the guibo and CSB lend themselves to be great vibration dampeners. Throw a solid shaft in its place and the dampening effect of those 2 parts is gone. A minor misalignment you may not have ever noticed is now an annoying vibration. Use a dial indicator with the instructions above ... shim the crossmember mount away from the body as needed and get those lines in order.

If you still have some vibrations left over after the above two conditions are met - use a slip yoke from an automatic Fox Body Mustang. Don't worry, the spline count is the same as the T5 yoke. Automatic yoke has a big round harmonic balancer dampener thing on it and should smooth out any remaining vibes.

[milehighXR]

The T-5 slip yoke and auto trans slip yoke are NOT the same. In all the North American A4LDs I have taken apart, the tailshaft was identical to the Merkur C3, and A4LD tailshafts except for the location of the speedo drive gear. The splined section of the auto trans is smaller that the T5. Elsewise we'd be able to use the Merkur slip yokes on our T5 conversions.

[merkurdriver]

The T-5 slip yoke and auto trans slip yoke are NOT the same.

I should have been a lot more specific; the (fox body Mustang) T-5 slip yoke and C4 auto trans slip yoke are the same.

[milehighXR]

Fox bodies did get A4LD near the end of it's run. Thanks for specifying that its the C4 that's the same as t-5.

[thesameguy]

Been looking at these a lot recently... the Ford T5 uses a 28-spline shaft (as does the C4 and AOD) whereas the C3 and A4LD use a 25-spline shaft. Most of the newer stuff (and some of the older, like C6) use a 31-spline shaft.