Why not just go with smaller tires?

 

3.21 is the same as 3.21:1 which means that for every revolution of the tire the drive shaft will spin 3.21 times.

 

**Deleted**--sorry wrong info

 

I believe those ratios are the internal gear ratios in the transmission. They will be the same regardless of the rear end ratio.

 

Thanks for the information on the gear swapping. I wanted a truck for the room since I am 6'4. I bought a 1500 crew and it has the 3.92. It was part of a tow package. I don't really tow anything. So I was looking to change out the gears for gas mileage. The salesperson did not explain the difference of the ratios and left me looking to change out the gears. I love the quickness off the line since I had a 05 300c, but I was worried about gas mileage and I felt the dealer got me. Now that I have read the post I am now content!!!

 

2009 5.7 crew cab, lone star . 3.21 ..... 321,000 on the clock. pulls anything i hook on to it

 

I could have bought a 2014 with 8 speed and 3.92 gears, but opted for the 8 speed with 3.21 gears and a hemi. I get 21+ MPG in slightly hilly mid-west hiway miles, about 15.5 in city which I am happy with. I can tow a 5000# travel trailer with ease. I can spin the tires at a light if I want to, but I don't want to. Cheap gas wont last forever. I opted for the mileage.

 

Sorry OP, but if you have 2014 or newer, there will be no gear changing for you. The rear carrier is welded and cannot be changed to 4.10's or 4.56's, believe me, I've tried. The reason you have 3.21's are because you have an 8 speed transmission. I have the 6 speed with 3.55's and the 8 speed beats me in a race every time. Your 3.21's are not as bad as you think.

 

just got back from pulling 5000# camper with my 2014 8 spd 3.21 gears... could not be happier... in tow haul mode shifting was smooth and steady speed with cruise on