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rear diff ratio - Yauchout - 09-30-2020

i have a international lonestar with 3.36's and 11r22.5 drives I tend to average 75-80K pounds running out of Alabama to either central Texas, Chicago, or North Carolina. I have seen a lot of info about that being a poor rear setup and was am having a hard time deciding if i should replace them with 3.55's or 3.70's and would like general thoughts


RE: rear diff ratio - tree98 - 09-30-2020

3.70 in my opinion


RE: rear diff ratio - Magard - 09-30-2020

How fast do you run and why 11-22.5 and not lowpro. I run 3.36 in one truck with 13spd. The other runs 3.55 with 10spd. Both get same fuel mileage. I run the 3.36 truck that is running the mandate in 12th gear out in California as needed to keep engine from lugging.


RE: rear diff ratio - Yauchout - 09-30-2020

(09-30-2020 )Magard Wrote:  How fast do you run and why 11-22.5 and not lowpro. I run 3.36 in one truck with 13spd. The other runs 3.55 with 10spd. Both get same fuel mileage. I run the 3.36 truck that is running the mandate in 12th gear out in California as needed to keep engine from lugging.

I generally run about 65-70. i originally ordered the truck for 75 in Texas for a dedicated route i no longer have that had tight delivery times. the dealer I ordered the truck from ordered it with 11r's and 3.36's they didn't give me much of a choice in the matter just told me its what I wanted for fuel mileage (which turned out to be shi#t anyway you cant run 75mph on tall rubber with such a tall ratio grossing 80K even the slightest hill requires downshifting besides that it beat the poo out of the truck and I'm paying for it in maintenance now )


RE: rear diff ratio - Magard - 09-30-2020

What transmission


RE: rear diff ratio - Yauchout - 10-01-2020

(09-30-2020 )Magard Wrote:  What transmission

A rtlo18913a so a 13 speed with overdrive


RE: rear diff ratio - Magard - 10-01-2020

I wouldn’t spend the money to change rears just run 12th gear. It’s not the most efficient gear theoretically but still viable option. Put lower pro on it next drive tires.


RE: rear diff ratio - 03maxpower - 10-06-2020

I went to 3:70 from 3:36 and I’m very happy with my choice.