allison rating

[cmtndmax]

An article dated 9/17/99 on TDP stated that the allison was rated for 545 ft. lb. & 375 hp. Are these correct? If they are then how can they last with the 800 or more ft. lbs. some mods make. For that matter what about only having 25 ft. lb. difference between the rating and what the engine puts out stock. I may be nit picking but past experience makes me appreciate over designing/safety factor.

[Maverick]

Those are correct numbers. How can it hold up? Don't know. Allison does make a great tranny.

[pinehill]

Both mechanical and electronic assemblies for critical applications are commonly either tested to their failure points, or their failure points are determined by analysis. These assemblies are then "derated" to a point where the failure rates will be acceptable for the application.

So, the designs of the Allison and other driveline components are such that they provide acceptable warranty claim rates at nominal hp and torque ratings. But the currently *published* numbers don't reflect any margins which may have been designed in for future model year power increases. How high do you think GM might push the stock hp and torque ratings in the sales wars? That's the point above which we can expect to see significant increases in failure rates by way of power boosting mods. And, of course, you may be thinking beyond the 36K and 100K mile warranty periods, which are GM's primary concerns.

[ 03-29-2003: Message edited by: pinehill ]</p>