[Bobs36ford]

Hi
I have a slight vibration going 30 MPH when engine is pulling. I have a 350 turbo auto trans.
I dropped the drive shaft and discovered there is a 1/3/4 inch play where yoke goes in to trans tail piece. Is that enough play to cause a slight vibration? The drive shaft in the car looks new and has been balanced.

Bob

[SSedan64]

If thats 1 & 3/4" inches of clearance from Yoke to end of Output Shaft it's way too much. Should be 3/4" to 1" of clearance.
Yoke could be wobbling & causing a Vibe.

[prostreet6t9]

How long is the slip yoke you are using? Sedan is correct... Normally you want it at 3/4" to 1".. But if your using a longer slip yoke that may not be causing the shake.

Verify that the shaft is the correct length and I would have the shaft double checked for balance.

[Bobs36ford]

Can the clearance be less than 3/4 inch... say 1/2 inch?

[prostreet6t9]

Thats cutting it kinda close.. What suspension do you have?? Is there any signs on the slip yoke that it has went all the way in and bottomed out?

Do you have a hard time removing the shaft from the car ?

[Bobs36ford]

yoke does not bottom out. Thats where i came up with a 1/3/4 " play.

Rear suspension is leaf springs and are pretty tight.

[prostreet6t9]

Originally Posted by Bobs36ford

yoke does not bottom out. Thats where i came up with a 1/3/4 " play.

Rear suspension is leaf springs and are pretty tight.

Sounds like you may be fine then.. Have the Shaft double checked for balance.