all these gear charts and your question always comes up. I dont trust the so called "better MPG" ranges on these charts. You need to get close to the original MPG range for the fuel economy.

we have one in our club that was 4.10 and 35 km2. it gets terrible MPG's and the power is absolutely terrible. we have to wait for him on the hills driving to the ORV parks.

You need either 4.56 or 4.88

 

^x2
The main thing you are missing is that those charts are mostly crap. If you are, or were, running 36 x14.5 15 bias ply tires the main problem is that the tires are extremely heavy which makes them harder to rotate than a 36 x 10.5 r15 radial tire, so a one size fits all chart isn't the answer. Plus those charts are for a 1 to 1 or direct ratio doing, I believe 65 mph, so a 5 speed manual with OD or a 4 speed auto with OD will be turning different rpms because of the OD ratio.

35x12.5 r15 will do much better as far as mileage goes than your current tire size.

 

Weight of the tire makes a difference too. Swampers are heavy. Try Pro Comp MTs, not Xtreme MT just the MT. Lightweight, easy to balance (one tire required no weight to balance, max weight was 2.5 oz), works in mud and rocks. And cheap. ~$200 from Amazon with free 2 day shipping if you're prime member.

Do you have auto or manual trans? 4.10 are about right with 35s and manual trans.

 

Auto trans and it has a lot of power with the 36x14.5 swampers so 35x12.5 so feel awesome lol
I found an almost new set of procomp xtreams 35s with procomp rims for 750 so I'm gonna buy them

 

Xterrains *

 

extremely weak sidewalls.

 

So they not worth 750 with rims? Or should I find something else? I really want the mtr kevlars

 

i'm loving my mtrs 35/12r15

there great in snow mud and on rocks.