Which gear ratio will get better MPG with bigger tires?

Question

I am looking at buying a V6 truck that comes with 4.10 gears. An optional gear ratio of 3.73 is offered/available. The 4.10 would get better MPG stock, BUT.......which one would get better MPG if I took off the stock 29" tires (+/-) and went to 31-32" tires?

I would like to put bigger tires on eventually (read...too many hobbies, not enough $$$) and don't want to regear if I don't have to. I am trying to plan ahead to know which gear ratio would net more MPG.

I don't tow anything, MPG is top priority. Auto trans. Thanks!!

Answer 1

the 3.73 gear ratio would get better gas mileage either way. basically the engine turns fewer rpms with a lower (numerically) ratio to drive at the same speed, which equals better fuel economy. adding the lager tires will also improve fuel economy somewhat, same principal, but you want be able to tell unless you calibrate your speedo for the lager tires. the 4.10 gear would give you stronger acceleration with the larger tires and about the same fuel economy as the 3.73 gear with the smaller tires. hope this helps.

Answer 2

The taller gears will always have the potential to better gas mileage. And going with larger tires is an additional step towards a larger final ratio.

However, this is potential - if you are doing everything you can to save gas, and driving mostly highway miles, then this would wind up being true. However, if you are driving more stop and go, the combination of heavier tires and taller gears could mean you will use more gas as you'll always be working to overcome the weight and trying to fight towards the engine speeds that are most economical.

You would be better served to pay attention to making sure your tires are properly inflated, going lightly on the throttle, and not running your AC! These would make MUCH bigger differences than taller tires.

And... if MPG is REALLY top priority, why are you looking at a truck?

Answer 3

you will see a power alleviation. for the reason that's a hemi that's going to shelter it ok. In concept you're able to get greater constructive mileage with much less power from the taller tires. regrettably the greater suitable rubber on the floor and greater wind resistance of the truck being greater up will kill any gasoline financial device hopes.

Answer 4

Yes it might lower the gear ratio,But they will also weight more. So you might not gain a thing. It will make the truck harder to stop so you might think about that for awhile.

Answer 5

what?