Best gear ratio for towing
I have a 03 2500 cummins srw quad cab with 3.73 gears, and wondering about changing to 4.10. I know it would tow better, but probably get less fuel mileage. Has anyone towed with these ratios. Thanks...
Forum Discussion
4:10's will give the OP better use of 4th gear in the 4 speed tranny and keep running temp's down by not lugging the engine or by running high 3rd gear rpm's at 60 mph ish.. If you are not running any 6% grades or higher then you won't benefit much. I need to do the switch and can see with gauges and slight mods to the truck where I'm actually at. The above statement is true regarding hp and torque but operating temp's are another thing to consider (egt's) especially if you have done any engine mods to make it run hotter/more powerful. Pulling a hill here in AZ in 4th and downshifting into 3rd reduces my egt's about 2-300 degrees. I also burn more fuel but it's def. happier.
