Coyote - Manual Transmission

[Digger556]

Weight also translates to increased time at a given torque load.

More time at higher torque shortens the life of bearings and gears. And the relationship is exponential. Double the torque and lifespan reduces by a factor of 4.

 

[jamesroney]

But...but...but...

In 4th gear, the transmission is a pass thru, and the torque is limited only to the diameter of the input shaft. ANY transmission can survive max torque for indefinite time at 1:1.

Which is why the NV4500 behind your Cummins should never be used for towing up long grades in 5th. But if you run it in 4th...it will survive forever.

Therefore, torque capacity and longevity is effected by gear selection. Which is one reason why the answers get complicated...