I have seen different rear end gear ratios discussed here here and read where some owners have changed their gears in favor of more pulling power, higher speed, or improved MPG. I don't know what mine is. How do I figure that out? Truck is stock. What is best ratio for improved MPG if don't do much towing? What ratio is best for towing if I'm rich or own a well? I have an 07 Dodge, 5.9 Deisel, 4X4, 6 sp, Mega Cab. Thanks much! Thomas

 

For your year model with the 6spd manual it's the 3.73. The only ratio available.
If your towing alot I say keep the same ratio.

MikeyB