'01 allison updates

[Showgood1]

What are the latest updates for the allison? My friend was useing his '01 to pull a tandem dual trailer loaded down with farm equipment. It did a awfull lot of down shifting. As we got closer to home it got darker and colder. It finally settled down then. I guess the cooler air helped the engine to produce more power. The highest the temp outside got the whole trim was maybe 60 deg anyway. The engine has a 4" exhaust but no other modification's. Rough guess is that the trailer the M5 moline and other junk wieghed about 10,000lbs. On the next trip we will be hauling a 210 Allis Chalmer it wieghs about 11,000 by itself. Did they ever solve this problem? If so what is the going rate for a update and do you have to have it done at a GM place or can it be done at any place that services allisons?

[Buck]

Mine is updated to '03 status. The first update was related to "busy downshifting with cruise control". It took the speed loss margin from about 2mph to 4mph. That helped a great deal at the time. It seemed to be do to turbo lag.

Since then got 4-5" exhaust, AFE stage II and the 90hp juice. Will pull 10,000lbs easy in overdrive without downshifting regardless of the hills. Turbo lag now is almost nil....

Don't know what the cost would be on updates, if any, assuming you have no warranty left. I would take it to the dealer tell them your problems. I've gotten updates with no warranty left/no cost. They will just plug in the tech II and can tell what you have/need as far as updates. Good luck ;)

[DmaxMaverick]

Showgood1

The "problem" you describe sounds more like adaptive learning, and is normal.

If you tow ocasionally, you can expect it to happen from time to time. The TCM/PCM "learns" your driving habits and adjusts the shifts accordingly. If you drive for a long time empty, then load up with 10K, it will shift different, and possibly more busy. After some miles with the load, the shifts will settle down.

If the truck hasn't had any updates since it was new in '01, they should be done, as there have been several improvements to the programming. It only takes about 15 minutes with a tech. that knows his way around a Tech II.