Transmission/Driveshaft moving towards the Passenger Side More since been on the Road

[DadofThree]

This isn't the typical "my driveshaft isn't centered" post.

This is a "my driveshaft has continued to move towards the passenger side" post.

27,XXX miles and I started getting a clanging noise under the transmission tunnel cover under acceleration or hard cornering under load. I took the transmission cover off to inspect and saw that my driveshaft has been hitting my safety loop. I took off the driveshaft and safety loop to inspect and put the driveshaft back on, but without the safety loop during testing.

NOW there is a buzzing vibration sound under there at certain speeds (40-50mph). I again took off the transmission cover to inspect and saw that the driveshaft universal joint nearest the transmission is touching the cables! This thing has shifted towards the PS.

I took a huge crowbar and was able to see that the transmission able to be moved back to a more centered position while still bolted in. I don't see any side to side adjustment slots where the transmission bolts onto the brace.

Has anyone seen this before? Ideas on where to look? Everything under there looks tight.

Thanks, Dave

[Ducky2009]

Sounds like a broken trans mount or the bolts from the mount to the trans are loose/missing. Slowly jack up the rear of the trans and see if the mount separates... is broken. Only life a little. If it doesn't separate, it may not be the problem. Also check the trams mount/frame bolts.

[SteveHsr]

FFR chassis with correct motor mounts locates crankshaft, transmission and driveshaft centerline 1inch toward PS from center.

[Norm B]

In addition to the recommendations above, check your motor mounts.

[Bob Cowan]

If you have a lift, use it to lift the engine and trans about an inch or two into the air. Check all three mounts, and replace/repair as needed.

Once the two engine and one trans mounts are repaired, lower the engine until it is just barely touching the mounts. Measure to get it straight, and then drop it in place. Getting the engine completely in the air will allow you to adjust position without friction or resistance.

Once down and tight, measure again to make sure it didn't shift.

[DadofThree]

Thank you for the responses. I'll be checking out the mounts. Hope to find something soon.

[rich grsc]

Sounds like a broken transmission mount

[totem]

This summer, after unloading the car from the trailer at the race track, I found a significant size bolt on the open trailer deck...

I was puzzled. Where did that bolt come from? Did a friend tricked me?

It was one of the two support-to-transmission bolt.

I would probably not have been a catastrophe. However, I was lucky that the bolt fell on the trailer and stayed on the open trailer. otherwise I would never have noticed this missing bolt.

Check if your not missing trans mount bolts!

[DadofThree]

I do have a broken transmission mount, but after replacement I still have the same problem. I'm wondering if it's a victim of whatever is going on.

Transmission support bracket is in place and all bolts installed. Drive shaft is touching the e brake cables even after new mount installed.

I still need to check the engine mounts

[BEAR-AvHistory]

Vibration might have shifted the engine.

[totem]

1. Move those cables away.
2. Loosen all 3 mounts
3. Tighten the transmission mount while prying away the transmission.
4. Retighten the engine mount.
5. Accept the remaining offset.

Steps 2,3 and 4 are optional. ;)

R.

[CraigS]

The engine mount to the frame end usually won't move much due to the locator pin plus stud/nut but give them a try. Then also try loosening but not removing the mount to engine block bolts to get a little more. It doesn't take much movement there to get an inch or two at the trans mount. You could even remove the mount and slot the holes slightly to get a little more.

[Walt]

That's what I had to do on mine to get it to move over enough.136706

[DadofThree]

Update: I found a broken motor mount on the driver side. The passenger side looks solid so I haven't change that out. But I think I will anyway. I was pushing to be able to take the Cobra down to meet a cobra rally this weekend but ended up taking my daily driver.

Now I am back home and looking at everything again. I will loosen the smaller studs to the engine without removing and see if I can wiggle the transmission of a place. If not, I like the slot idea.
All this with a stock 302!

Thank you for all the help

[DadofThree]

PS Motor mount is bad too!
That's 3 for 3 on the mounts!

I took the new part out of the box to compare.
The new one has a considerable gap at the base of the mount. But the one in place on the Cobra; it's gap has collapsed.

I'll do that tomorrow, then plan on a cruise!

[Rook]

Glad you found the problem(s).

I like your painter’s tape method for keeping track of your to-do list. Seems like a good way to ensure you don’t hop in for a drive with anything loose or un-filled!

[DadofThree]

Third mount replaced. Unfortunately for this one I had to remove the passenger side headers in order to get the mount out. I was able to do that and swap the passenger side motor mount. Everything is back together and buttoned-up. The safety loop is around the drive shaft again and it looks as though I have plenty of room on both sides of the drive shaft. I'm off for a ride!

[DadofThree]

Took her for a ride, and she did great!
There was no interaction with the safety loop.

I dropped her in 2nd a couple of times to launch from a slow roll and had no interference.

I really don't know why I had to replace all the mounts, but it's done and was indeed the solution. Thanks

[CraigS]

It's always nice to read of a good solution to a problem. Thanks for the report.

[Jeff Kleiner]

I got your voicemail Dave and was just checking back on this before returning your call but now that I've made it to the end it looks like I don't need to call back! Happy to hear that it is resolved :)

Jeff