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
USMA Dad wrote:
While were on the subject (yet don't want to take over the OP), let me ask y'all this: I'm in a similar situation. I have an '04 2500 5.9 CTD, 48RE tranny, and 3.73s 2WD. Stock tires are 265-70-R17. I'm towing about 16,000 (loaded) with a pin weight of about 3,800.
I added two springs on each side to compensate for the pin weight and increased my tire size to the Michelin XZE 245-70R19.5 (33") for increased tire rating (best I could find in a 17 was 3750). Since I increased the tire size, I've taken my 3.73s to somewhere around 3.5x. The engine also runs around 208* when towing. I have a Bulldog Juice with Attitude and tow in the tow mode.
All of that for this, would I benefit by moving to the 4.10s? If I do make the change, I think I'm back closer to the 3.7x area. My main concern is I have a long trip to NY coming up in May and will have a some sections of grade to contend with. What say all???
BTW, this is a "gearing" question, not a "weight" question! :B
Look at the ratings for your MY with your "new" effective gear ratio. Probably the closest offered was 3.42. IIRC It had a dismal 8800# rating. With your tires, you probably should be in the 4.30 area for max towing.
