Quote Originally Posted by TJNE View Post
I read on the Diesel Page that their are 3.42, 3.73, 4.10 gears in ref. to MPG and towing weights. Did I misunderstand or am I missing something? It recommended for towing heavy the 4.10's and for MPG 3.42's. Thanks again.
That applies to previous engines, 6.2L and 6.5L. It could apply to repowers of other vehicles (with a Duramax), as well. If the truck you are looking at is stock, it will have a 3.73. The Duramax trucks do very well towing very heavy with 3.73 gears, and do well on mileage with the same.