I have an 06 LBZ with the auto 6 speed trans. When im driving say about 10 miles an hour and let off the throttle and then when im still moving get back on the throttle it seems like the trans engages sorta hard even when im real light on the throttle. And also when it goes into 3rd it doesnt grab it right away it has like a half second pause where you hear it shifting. Is this anything to worry about or am i just over reacting? and another side note, when im driving down the road it seems like im always having to compensate the wheel because it feels like its swaying back and forth a little bit. Just had an allignment done and tires rotated. Could it be that i didnt replace the bad clunky intermediate steering shaft yet or is it something else? thanks guys

 

The Allison is a smart trans, it will adjust it's shift patterns to your driving style. Do you have anything done to it? or motor? If you aren't pushing a big tune, these trans will last just about forever. If you do have a tune, it's best to do a re-learn on it, and drive it how the re-learn suggests. That might help the shift issues you are feeling. When doing the relearn, it might feel clunky and jerky for a little bit while it adjusts.

 

One of the first things to try is the filters. Trans and fuel. The transmission can start acting weard when they start getting plugged up

 

The truck is completly stock as far as i know. The previous owner might have had a tow tune on it since it hauled about 10,000lbs plus the truck wiet itself its whole life. But it seems like the 3rd to 4th isssue goes away for the most part when the trans temp reches above 150 degrees.

 

does anyone think it could be a bad c3 clutch pack?

 

that is a god possibility as the C3 is the weakest clutch pack. the transmission can do some weird things when the clutches are burned.

I would give your nearest reputable Allison shop a call and pick their brains.

inglewood transmission (714) 870-7300 in southern California is the nearest to me and one of the best in the business.

 

Ha that'd have to be about the farthest from me i live in PA