OK, now I really need advice on MPG!

[AKElroy]

I know this thread is probably overdone, but I am curious regarding my recent mods KILLING my mileage. I recently mounted 305/65/18 AT KO's on the stock rims, replacing the stock 275/65/18's. I also installed the ReadiLift 3" front / 1" rear level kit. Mileage has tumbled from 13.5 / 14.5 to 10.8. Even correcting for the larger tires, I am getting a true 11.4 MPG. My driving style has not changed. I keep 40lbs all around, and this has the new AT's slighty domed (they are mounted on stock rims .5" narrower than recommended) so I do not want to go with higher PSI lest they center-wear prematurly. Is it possible the fuel / shift mapping is incorrect for these larger tires? Do I need to do a computer reset? If so, should I tie the cables together? Am I missing something else? The only other mod to the truck is the charcoal delete when I first purchased it. Need help--I actually need the lift & tires for a recent deer lease acquisition that is similar to driving on Mars. 2007 Crewmax 5.7 4X4.

[rockstate45]

Just gotta live with it. I see 12 with my grille guard (112 lbs) and my 285/65/18. You could probably gain some extra mpg with the 285/65/18 but it's really not worth it, specially if you have to spend another $1400 and then sell your current ones, which you probably paid out the @$$ for.

Long and short of it, with every action there is a consequence. You need a lift and big tires, you will get extra rolling mass and extra wind resistance. Nothing you can do about it, except stop at every other gas station you see. These tanks are just too small to do any driving with 'em.

I drove a brand new '09 F150 SCrew Lariat 4wd with 531 miles on the clock. It was averaging 10.5 mpg and STILL had 331 miles left on the tank WITH 1/4 of the tank gone. I can't get 300 miles out of my tank ON THE HIGHWAY!

-rockstate

[AKElroy]

I know that is probably the only answer, but I am hoping for a miracle response like "dude, just do X & truck will adjust to those bigger tires". That would be great Any other advice would be helpful. If we go back to $4 gas, this rig gets parked & I buy a prius, heaven help me.

[rockstate45]

Originally Posted by AKElroy

I know that is probably the only answer, but I am hoping for a miracle response like "dude, just do X & truck will adjust to those bigger tires". That would be great Any other advice would be helpful. If we go back to $4 gas, this rig gets parked & I buy a prius, heaven help me.

haha, I think the best bet would be to buy that bigger gas tank and remove the cap on the credit card

Ah, what I wouldn't give to have a factory option of a bigger gas tank....without having to pay $1000 for one.

-rockstate

[mxsjw]

Originally Posted by AKElroy

"dude, just do X & truck will adjust to those bigger tires".

Dude...Hypertech speedo recalibrator!
That and keep it shifting under 2000 rpm. (tie a string from your right big toe to your twig and berries if that'll help you ease into the throttle)

I've got the same tires with a similar lift on my 5.7 DC and I still get 16 to 17 mpg on the highway in the summer.

[RamItOne]

drive downhill

Youshould have bought a 4 wheeler, I've got a 800 acre lease in San Saba and was thnking about lifting and putting on a winch, then decided to buy a 4wheeler instead. It'll get into more places than the truck could ever get.

Good luck, as long as you get a lil stiff every time you see yer truck then it's all worth it.

[AKElroy]

Dude...Hypertech speedo recalibrator!
That and keep it shifting under 2000 rpm. (tie a string from your right big toe to your twig and berries if that'll help you ease into the throttle)

I've got the same tires with a similar lift on my 5.7 DC and I still get 16 to 17 mpg on the highway in the summer.

I have been recalibrating manually; is their a programing reason to go with the hypertech (beyong the convenience factor?) What PSI are you running in your AT's? Lastly, any benefit to running higher octane?

[escondidotundra]

not sure about this, but I don't believe your fix is here yet. You need to re gear the rear end. front dif if you are 4x4. I don't think they make gears yet. When they do, get a set that are a little more aggressive than stock and you will see your mpg raise at least enough to notice.

like an above post said, re calibrate the speedo. do that asap, at least it will shift where it is supposed to, that will help, but not like re gearing.

good luck

[AKElroy]

(tie a string from your right big toe to your twig and berries if that'll help you ease into the throttle)

Maybe I'll just live with it instead.

[mxsjw]

Originally Posted by AKElroy

I have been recalibrating manually; is their a programing reason to go with the hypertech (beyong the convenience factor?) What PSI are you running in your AT's? Lastly, any benefit to running higher octane?

Gets the speed based shift points back closer to stock.

I run 45 to 50 psi in mine on the stock TRD 18's, they're not domed and showing no obscure wear after 31,000 miles. In fact, these tires look like they're going to last me somewhere around 70k. Rides like a truck, you feel the bumps at this psi...I like 45 psi better, but they are at 50 right now cause I haven't lowered the pressure since my last tow and week or so ago.

87 octane is all I run, most of the time from the Safeway Grocery Store Station.

[RamItOne]

You should be glad toyo went crazy with the gears, dodge offer 3.55 3.73 3.93(3.92?) 4.10 with their trucks, think the powerwagons came with 4.54 (remote auto locker and remote swaybar disconnect mmmm) most of the ram guys I know go with 4.54 when they upgrade, but with our trucks coming 4.30 w/ tow package I doubt someone will spend the time to machine mid 4.xx gears as the cost would be significant for minimal gain, so there'd be just a small market, now 5.fx I can see for the people with 37" tires, in time, gotta have more toyos on the road that first.

And yes using a CPU to adj speedo with get yer shift points back close to stock.

[ArtM]

Originally Posted by mxsjw

Dude...Hypertech speedo recalibrator!

So what else will the Tunbdra Hypertech do? For some trucks one can even reset the rev and speed limiters. Does the Tundra Hypertech do anything besides the Speedo recalibration?

[Fromanhb]

I just installed Bilstein adjustable 5100's (set at 1.75" of lift) and threw on some 305/65/18 BFG A/T KO's and went from 15MPG to 12MPG (this is accounting for the 4.8% difference in speedo between stock tires and new ones)

The tires are the real killer... I had the lift on for a couple of weeks before I bought the tires and my mileage stayed the same. However, once I put the new tires on I lost HUGE mileage. Kind of a bummer since the tires themselves cost $315.00 each with the added benefit of draining my wallet more then I expected at the pump.

[music]

Originally Posted by mxsjw

I've got the same tires with a similar lift on my 5.7 DC and I still get 16 to 17 mpg on the highway in the summer.

Most of the economy is lost during acceleration, climbing hills, etc. Those big tires change the power/gearing tuning, which is optimized for the OEM tires. I'd expect similar mpg on the highway compared to a smaller tire with the same tread, but not around town.

[RobertT3]

I respect the lifted trucks but for poor mpg I'm gonna pass..I rather stay low and be fast.. I'd get a diesel if I'm gonna get my truck lifted..Buddy sold his CM recently not even a year old that he lifted months ago..that sucka looked great! climbing up @ off of it was a pita sometimes!hehe..and poor gas mileage was kicking his a** so he traded for nother Tundra but staying stock this time..maybe bigger tires thats all..dont blame him..I'm keeping mine stock w/ just a leveling kit can't imagine loading my sportbike on a lifted Tundra..thatd be a scary moment!

Good luck!