So i recently installed a g-force t5 for my 66 mustang 289. I purchased the conversion kit from cj pony parts. http://www.cjponyparts.com/t5-transm...1966/p/T5CK15/ since the swap i have noticed some pretty bad vibrations at mid to high rpm in 1st, 2nd, and some of 3rd gears. The only thing i see that is a little bit out of the ordinary is with the new "shortened" driveshaft. from the rear seal of the trans to the base of the slip yoke, i am seeing 1 5/8' of gap that just doesnt sit too well with me. could this be my issue? I took a picture of the tailshaft with the driveshaft yoke, but i cannot for the life of me figure out how to post it.... could use a little help here too so you can see what i am talking about with the yoke...

thanks.
Mike

 

ok heres a link for the picture....

http://s919.photobucket.com/albums/a...ent=photo2.jpg

 

Does the vibration happen in gear and out of gear?

 

He's a picture of mine with my T-5. I had my drive shaft balanced as well. Your gap looks a bit more than the gap for mine. What size rear end are you running? Maybe your is a bit smaller and makes a gap at the tranny end bigger.

 

Nope. Just when it's in gear and under load. At idle in neutral motor is smooth. Which is making me think the drivetrain is the issue, and that's then only thing that really stands out to me...

 

Hey musnicki, yours looks totally normal to me. Which makes me suspect even more that this is my issue... Can a driveshaft be lengthened? I know they can be shortened...

 

Yes they can be lengthened.

try this. support the car on the chassis on jack stands. then cylce the rear suspenision from compression all the way to full droop. If there is still 3/4 of yoke on the other side of the trans seal at full droop you don't need to lengthen your drive shaft.

 

I took that picture with the car on the ground.... I understand there should be some room for suspension travel, but 1 5/8" with the car on the ground just seems like way too much. It stands out, ive never seen that much yoke on any trans and driveshaft... I dunno maybe I should have the driveshaft lengthened 1 1/2" and go from there?

 

I had the same issue. I went through EVERYthing. I found the issue by putting the rear of the car on jackstands and starting it and putting it in gear so the tires will spin. Then I got beside the car and inspected the drive shaft. I also put it on video with my phone. Check out the post I did. It ended up being my brand new driveshaft. It was way out of balance. So they built me another and bam. Problem solved.

 

It looks like enough is not engaged, but it could also be the drive shaft is not balanced well.