Allison 5sp: trans problem?

[Max Attitude]

Hey guys

On the truck listed in my sig.... Often but not always my truck shudders when it shifts. I have 130k on the stock trans and run the Predator on 85 right now. I had this problem a while back too. Back then, I cleaned the air filter and MAF, changed the spin on filter and it seemed to go away for a while. It came back again.

-I added the spring clamp mod and it seemed to lessen the shudder by 50% for a little while. Now its worse again and it drives me nuts.

-It seems to shudder less when I am heavy on the throttle vs mid throttle.

-In the past I tried putting the tune back to stock and the shudder was worse.

-Been running Amsoil Torque Drive since about 85k.

 

[Max Attitude]

No one?

If I let off the gas and hit it again while driving I feel it too. Feels like the drive shaft bounces almost. So its seems maybe not the trans. Could it be the converter or something in the transfer case? I have the Mike L pump rub plate.

I checked the u-joints and they are tight and the caps feel fine.

 

[whitetrash21]

I guess converter. A trans thats been beat on for a while will shudder.... mine does if i pin it hard in 1st pr 2nd ..... once converter locks, its gone .


Btw mines in t/H 24/7.... if that makes a diff.

The wheelhop shudder feels the ass end of the trucks falling off.

 

[Max Attitude]

So I went up to the dunes on Memorial day, beat on the truck a bit and on the way home it shifted perfectly... no bounce or sloppy feel, just smooth shifts.

I use tow haul a lot too especially with a lot of stop and go driving to use the brakes less.

 

[Max Attitude]

Looks to be a broken motor mount. I power-braked it while a friend looked under the hood and the motor lifts at least 6'' on the drivers side.

 

[Mike L.]

You may have found your problem.

 

[Max Attitude]

I believe so, time will tell.