Interested in gettinga 6.0 question bout gears

[Cociorvan]

I have never owned a diesel, but want one cuz I love them I've driven friends diesels andwant one for myself anyway im looking for a daily driver and have read all the fuel mileage posts but I was wondering would it be possible to put 3.55s in a truck to increase gas mileage? I dont plan on racing it or hauling just a daily driver, thanks for any input.

[colo_dually]

3.55's are doable in the 6.0L, however you will be placing extra wear and tear on the driveline and transmission. Figure the cost of the gear swap, you'll have to put a lot of miles on the truck to see any return on investment. Between the extra wear and tear, and the minimal gains in MPG on the highway (you will see a reduction in city mileage in traffic and stop-and-go). I doubt you'll see any gains when you balance the costs.

[Cociorvan]

Alrite thanks for the input im just trying to figure out how much mpgs out of it

[mustangman02232]

do you have 3.73s now or 4.10s? what about going one size bigger on tires?

[Cociorvan]

I dont have a truck yet im still shopping around I just wanted to no if 3.55 would help out with mpgs alot or not, im tryin to get everything all figured out before I actually get a truck

[Cociorvan]

now colo_dually is this extra wear in the transmission? if so is it because of all the upshifting when having to accelerating in traffic lets say? and if thats the problem could i get that fixed with a custom tune? When i do end up getting the truck i plan on keeping it till it dies on me

[colo_dually]

Higher gears put more stress on the drivetrain in general, moving from a stop, shifting, all of it. The reason that the 2011's can come out of the factory now with 3.55 and 3.33 gears is because the new 6 sp Automatic has a much lower first gear than the 5R110 TorqShift.

All the SRW's for the 6.0L came with 3.73 gears, (it was 4.10 or 4.30 for the duallies) keep the stock gears and stock height if you plan on running it until it dies, and get the truck bullet-proofed. Use a tuner to see the mileage increased, I'm seeing a 2 MPG gain with my race file and keeping myself out of the throttle.