5th gear vibration issue

[mazspeed]

Ok, so I have been having this problem with the car, and I think Kevin at CAR figured out that where the car is in motion in 5th gear, it will vibrate at higher speeds. It will do it down low a bit, but it's more pronounced at 85mph and higher. The tranny came from Keisler, and they told Kevin it was out of warranty, but they didn't shut the idea of them fixing it either. Don't know about that yet. My question is, do they have to rebuild the tranny for this, and what could be causing the issue? It's a TKO-600 in case you anyone was wondering.

[Vegas69]

First thing that comes to mind is driveshaft.

[projectile]

First thing that comes to mind is driveshaft.

I second that! My problem was pinion angle.

[mazspeed]

Pinion angle was good, brought the car up too 85 in forth gear with no vibration, 5th had the vibration at the same speed. I also thought the driveshaft as well.

[projectile]

Can you feel it through the shifter?

[mazspeed]

I have not really noticed, or tried to notice if the shifter is vibrating more then normal. Maybe I should.

[Spiffav8]

Can you feel it through the shifter?


I have the same problem only at 65ish and I feel in the shifter. I'm thinking drive line but could it be the pinion angle?

[mazspeed]

I have the same problem only at 65ish and I feel in the shifter. I'm thinking drive line but could it be the pinion angle?

I think the pinion angle is 2-3 degrees, the way it's should be. They made sure and checked it.

[Blown353]

Several things come to mind to check...

mismatched front to rear u-joint working angles

excessive u-joint working angles (this is the cause of my high speed vibration, I need to raise my entire tranny tunnel for more driveshaft clearance so I can raise both the tranny angle and rear end angle to minimize the total u-joint working angles.)

runout issues on either slip yoke or pinion yoke

worn & loose output shaft bushing in transmission

driveshaft runout / balance problem

If it's speed related and not RPM related as you said (the vibe occurs at a given speed no matter what the gear) that pretty rules out the clutch & flywheel as the problem and points to the driveshaft on back as the source of the problem.

It could also be a wheel, axle, or bearing problem too.

[mazspeed]

Several things come to mind to check...

mismatched front to rear u-joint working angles

excessive u-joint working angles (this is the cause of my high speed vibration, I need to raise my entire tranny tunnel for more driveshaft clearance so I can raise both the tranny angle and rear end angle to minimize the total u-joint working angles.)

runout issues on either slip yoke or pinion yoke

worn & loose output shaft bushing in transmission

driveshaft runout / balance problem

If it's speed related and not RPM related as you said (the vibe occurs at a given speed no matter what the gear) that pretty rules out the clutch & flywheel as the problem and points to the driveshaft on back as the source of the problem.

It could also be a wheel, axle, or bearing problem too.

It's not speed related. in 4th gear at 85mph it doesn't vibrate at all. In 5th at the same speed it does vibrate. I have new wheels and I did watch them being balanced and they are lazer straight. Does the drive shaft spin more in 5th gear at the same speed as it would be in forth gear at the same given speed? I don't think that's the case, but I don't know.

[Vegas69]

It sounds like it's more rpm related. I would take the rpm you run in 5th at 85 and see if the same vibration is there in other gears at the same rpm. It could be a by product of the engine combination or harmonics through the mounts at that rpm. Could be the tranny but would exhaust other possibilities.

[kp.touring]

Hey guy's
Just to let you know the vibration is only in 5th. We have checked pinion angle and adjusted it, then ran the car at the same rpm as the vibration in the other 4 gears to rule out anything in front of transmission and then ran the car at the same mph in 4th gear to rule out evrything behind the transmission. The vibration is in the box.

Kevin

[kp.touring]

Just an update on Mike's transmission vibration. Keisler is going to repair his transmission under warrenty.

Kevin
CAR

[mazspeed]

Thanks Kevin for taking care of that for me. You guys do go that extra mile. Also thanks for taking to Hector at Rick's hotrods and for them to also fix my tank.

[awr68]

Sounds like the to-do list is getting much shorter!! Did we ever get the motor dialed in? And if so Dynoed? Where's my vid?? :)

[mazspeed]

Sounds like the to-do list is getting much shorter!! Did we ever get the motor dialed in? And if so Dynoed? Where's my vid?? :)

Hey Anthony. The list is very small and it's being addressed right now. The tank is going back to Rick's for rebaffling, the tranny is going back to be addressed, the water injection was not shooting out much water at all. 5 tanks of gas, and it only went down one inch in the tank itself, and a 10 pound boost pully. And to fix the right side headlight door, that's pretty much it at this point. I have had a hard time getting a video camera.

[RBR]

This thread is kinda scaring me I'm looking to buy a new tranny now. tremec 5 speed:_paranoid

[mazspeed]

This thread is kinda scaring me I'm looking to buy a new tranny now. tremec 5 speed:_paranoid

Tremic is really the best tranny for this kind of car. Don't worry about a few issues with a few people. It's a bad ass tranny. Just happens to be an issue with mine.

[Clockwork]

Tremic is really the best tranny for this kind of car. Don't worry about a few issues with a few people. It's a bad ass tranny. Just happens to be an issue with mine.

Please report back here with your results :thumbsup:

[mazspeed]

Please report back here with your results :thumbsup:

I will. :thumbsup:

[mazspeed]

Quick updtae, this is the e-mail Keisler send me. I want to thank them for helping me out. I do have to pay for the parts, which is not much, but they took care of the issues we had.

Mike:

As per our conversation a few minutes ago, here is an e-mail giving you the issues we found wrong in your transmission. The main issue was whoever switched the front retainer to the modified retainer, in order to run the hydraulic clutch, forgot to re-install the input shaft shims. When you pull off the retainer, the input bearing race and the shims will come out with it. There would have been anywhere from 1 to 4 shims ranging in size from .010” to .040”, pre-loading the input. Without the shims, shifting would have been difficult at best and the noise created would have driven you crazy.

Because the shims were missing, there was no load on the input which keeps everything “tight”. Without them, the engagement when shifting was VERY loose and caused damage to input shaft, race and shift fork pads.

There is also strong evidence that the bell housing run out was not performed, or if it was, it was not within spec. The tip of the input shaft that goes into the pilot bearing was glazed over in an uneven pattern. This is caused by the input shaft not being perpendicular to the back of the crank. In other words, the input was going in at an angle into the pilot bearing and crank.

We replaced the input shaft, input shaft bearing and race assembly and all 9 shift fork pads. We bench tested and leak tested it and everything shifts like butter now. It held pressure at 8.1lbs for 62 seconds which is 2lbs over standard and 30 seconds beyond spec(basically that means it passed with flying colors). I have also included 2 new pilot bearings at no cost as we need you to replace the pilot bearing in the crank. When you remove it, please inspect it for damage like I described and let me know what you find. You will also need to perform the bell housing run out procedure again and call me with the numbers so I can make sure we are within spec.


That's it for now.

[mazspeed]

Please report back here with your results :thumbsup:

Tranny is back in, and it runs great. No vibrating at all. :D

[Clockwork]

Glad to hear it! :cheers:
I'm pulling mine back out to dial it in. Hoping to get rid of my vibes.