Vintage Mustang Forums banner

1 - 8 of 8 Posts

·
Registered
Joined
·
124 Posts
Discussion Starter #1
Hello all..
Hoping to get an opinion from the collective knowledgeable mustang owners. I freely admit I’m no mechanic..

Backstory.. I bought my 66 last May, 400 miles will a full resto on it. All new driveline.. I put almost 1000 miles on it during the summer, then last fall I developed a leak from the tail shaft from the T5. There wasn’t any vibration in the driveline, pretty smooth all the way up to 100, (only once ;) ).There’s a mechanic in town that was recommended by 3 people so I took it in. Bought what I thought was the right seal, he dropped the driveshaft, put in the seal...still leaked but still smooth. Tracked down the right seal so once again he replaced it. Good news, no more leak, however I felt the vibration from the first drive. He looked at it and suggested the driveshaft could be out of balance. It was fall and time to park it so I’ve waited until the spring.
Woke her up a week ago or so, so asked him to drop the shaft back out and double check it.. unfortunately at just about 45-50 mph the vibration is still there. So he wants to drop the shaft and send it to a local shop for balancing. Suggested the unbalanced shaft could have caused the leak, Everything else looks good under there, but wondering..

Is it possible that an unbalanced shaft cause the leak in the first place, and a new seal now causes the vibration?

I guess now it’s a matter of elimination, but Any thoughts on a possible alternate cause of the vibration?

Thanks!
Forrest
 

·
Registered
Joined
·
320 Posts
While an out of balance or bent driveshaft could cause the seal to leak, so could a failing bearing in the tail shaft of the trans. Providing the seal surface on the yoke is good.
That all said, if it didn't vibrate before the seal replacement, it shouldn't do it after. I would think when you took the car back, the mechanic would have checked to be sure the u joints were seated in their saddles correctly, but that would be a possibility.
 

·
Premium Member
Joined
·
3,375 Posts
If not remedied by just turning the driveshaft 180, and reinstalling, check the condition and tightness of the trans mount and of course, the U-joints. Also be sure nothing is rubbing the exhaust .
 

·
Registered
Joined
·
124 Posts
Discussion Starter #6
Thank you for the suggestions. I’m hoping to get it up in the air this weekend rotate the shaft and take another look. The fact that it just started after he replaced the seal seemed suspicious to me, but wanted to ask. I’d like to believe he checked it thoroughly last time, but I have another mechanic that could give me a second opinion..
 
1 - 8 of 8 Posts
Top