Fisherguy

Interesting, I'm looking at 35's myself right now, but with my stick I'm hoping the drop in revs on the highway will give me mileage about the same as what I'm getting now, better if I drive only highway?

woodrep

Fisher, you should be ok with 35's and a standard. Just keep the boat stacked on the roof to help with the aerodynamics!

CD in NM

I'm getting 19mpg with my 35's, BFG's - 315-70-17. Have the 6-speed and 3.73 ratio. Bottom end is good, usually start out in 2nd w/o any problems. They drop the rpm's right into the sweet spot for 65mph driving. Towing my 5th wheel is 16-17, but its old and has NO aerodynamics - barn pulling barn. NO programmer.

CD

Farmboy89

Dad runs 35 12.50 hankook rf10s and a superchip and gets 17

Swayse

My mpg went way down with the 35" Toyo mt tires too, seemed like the truck was bogging when I was doing 70 mph. I added the smarty and gained 2 to 3 mpg, and the boggy feeling was gone.

Later, I went back to 285/70R17 tires and took my lift down, expecting a big mpg increase, maybe .5 to 1 mpg better with the small tires.

If you're stock and add big tires, you will lose big mpg. If you have small tires and add a smarty, you won't gain much mpg. See where I'm going?

Fisherguy

Yeah, I think so, that's good to hear though.
One thing though, my truck with the one boat on JUST fits into my garage with the 10 foot door, me thinks with the leveling kit and bigger tires I won't have that option anymore...

... it's still somehing I gotta do though, I hate the tilted thing that's goin on and when you lift the front it just don't look right with 285's.

(I just wish the tires weren't gonna cost my $1750 cdn)

Tobin

I just bumped the Smarty up to level 3 last night and it seemed to loose that boggy feeling, and the overhead is going up. Will run it like that for a while and see what happens. Can't wait for a Georend trans and run the Smarty on level 5 all the time.

Tobin

coblanchard

Hand calculate your mileage to know what you are actually getting, then let us know

Tobin

You can watch the gauge vs. odometer to get a idea that it is off from before.

Tobin

Hintz

I filled up today and I was at 19.45 mpg, with 35 BFG's AT's.

woodrep

Fisher, you need to jump or swim across the border and pick your tires up in the U.S. That's crazy money eh!?!?! What's that like 1200 U.S.?

Fisherguy

It's crazy Woody, $1750 woulda been the price for the Vortrac (E rated) at 376 each, now I'm thinkin of the Pro Comp XT AT's which are 410 each up here (but only D rated but I hear they're heavy ballsy tires?)

I'm going to see about a mail order place, I have a bud just over the line I could have them shipped to, but then I'd hafta pay CDN taxes and enviromental fees at the border.

If I had some totally bald tires I could just have them installed down there do it that way.

(BYW, 1750 CDN = 1386 US)

blowbyu

My best mpg was 23.7 highway it was with 35 in bfg all terrains, smarty level 9, fully built georend trans, industrial injection silver bullet 66 turbo, stock injectors, stock cp3, fass 95/150, afe intake, mbrp 4in exhaust on the highway at 70-75 i personally think bigger tires help

powermad

make sure your tire pressure is correct and your truck is aligned and tires balanced. since they are new im sure the dealer did all this but sometimes they dont to it good. plus you went to a bigger tire bigger tires mean lower mpg

Ace

This is all generally true, with a couple caveats. Don't forget about the tread pattern. MT, and even AT's to some extent present more rolling resistance than a highway tread. The stock tires are what, 32"? They didn't just throw the dice and decide to use that size tire. It was chosen for a reason. 33-34 will give a slight increase on the highway. But you'll lose it in town, so it's a wash unless you drive mostly highway. 35" is the size around where you are going to start seeing all-around mileage loss, no matter what - with the possible exception of 4.10s and a manual strictly highway - again, depending on all the other factors, tread, etc..