TKO 600 shifter vibration in 4th

[Grubby]

I made a mistake on driveline angles and just double checked. I zeroed my digital gauge perp to the car and then rotated it 90 degrees and took the reading. The car is not level to the ground.

Driveline angels are; pinion = 0.9 deg up, trans = 0.5 deg up, driveshaft = 0.4 deg down.

John

[CobraEd]

Originally Posted by Grubby

I made a mistake on driveline angles and just double checked. I zeroed my digital gauge perp to the car and then rotated it 90 degrees and took the reading. The car is not level to the ground.

Driveline angels are; pinion = 0.9 deg up, trans = 0.5 deg up, driveshaft = 0.4 deg down.

John

That could be it.


.

[Jerry Clayton]

Drive shaft is down from which end????
The trans and pinion angles should be equal and paraell---both of yours are up---

[lovehamr]

I posted this in an earlier thread but thought that it wouldn't hurt to post it again here. I to trimmed the nose of my TKO600 just like Wayne did. However I ran into another problem in that the splines of the I.S. actually touched the pilot bearing. If I hadn't been looking through the starter opening on my B.H. I wouldn't have noticed as the interference would have been taken up while the tranny bolts were tightened with no discernable increase in resistance. This is what the I.S. looked like when I got done:



BTW, my setup is 428 block, QT BH, TKO600.

Steve

[Grubby]

Trans input shaft is higher than output. Pinion is pointing up towards the radiator cap. They are .4 degrees from being parrallel. The driveshaft is higher at the pinion and lower at the trans.

My driveline angles are relative to each other. The car is on jack stands and I took no effort to level it.

Kiesler tech suggests bringing the pinion angle down .4 to be parrallel with trans angle.

My plan is;
1. adjust pinion angle per Kiesler
2. confirm eng/trans are parrallel to frame rails
3. confirm drive shaft balance
4. pull trans and look for contact with pilot bearing or crank

Do you think if I loosened the trans bolts and wiggled it back 1/8" then put some shims between the trans and bell to hold it back it would tell me if I had contact. I could drive it with the shims in place. If the vibration goes away then pull the trans and repair. If not, remove the shims and tighten the bolts back.

John

[elmariachi]

Possessing test pilot DNA, I'd shim it with some big thick washers, crank the bolts down and have wifey follow you for a quick spin. Probably not the safest move, but operating a Cobra in general is arguably not very safe either. This of course after you try the pinion alignment. I'd be surprised if .4* deviation would induce such a vibration given that you have a tight driveshaft and new driveline components. I guess anything is possible.

[Grubby]

I spoke to Doug at ERA and he has seen this exact problem one time. They changed transmissions and fixed the problem.

I decided to get a third opinion before doing a lot of work and drove to a friends house to take him for a ride.

With 47 miles on the trans the problem went away. The shifter exhibits little to no vibration in all gears. I put an additional 20+ miles on at many speeds with no further issues. I am baffled, but happy.

This trans did sit for a few years dry. My theory is something was stuck or rusted and when my gear lube heated up it freed up.

It seems crazy, but the problem was real.

John