Mine has gotten great milage since I parked it and went to Korea!

 

Uh, why do they put the "2" right next to the "3" on the keyboard? An obvious typo. It is a 3.73 rear gear, of course.

 

16 at best (70 mph flat grouind on cruise)
20,000 miles
G56
245 70 17's

looking to go with 265 70 19.5's to help get the rpm down and the fuel mileage up.

At 70 mph I am running about 2500 rpm. I have to run 55 in order to get down to 1900 rpm ,which will get you run over.

The 245/70-17 sucks!

 

Best I ever did was 17. Still good for a truck with gears and tires like mine

 

My average, at 75mph, is 19-20mpg. My absolute best, at 60mph, was 23mpg. I wish I could drive 60mph all the time......

 

I will agree. I am running 265-70-17's and i think those are too small on the 4x2. When these wear down and time for new tires I am going with 285-70-17. As long as you dont go to a wider tire, you will get better fuel milage with a taller tire to a certain point. Seeing that mine came stock with 265's i think I will gain 1-2mpg going to 285's. My overall goal is to get 30mpg.

 

I just installed a set of E rated Toyo 285's so no mileage report. Hope to bump up the fuel economy, especially out in West Texas where the speed limit is 80.
I say don't wait, go ahead and get the new tires.

Trying to get 30mpg is pushing it though......

MikeyB

 

any 2wd mpg with after market ring and pion - higher ratio - or the two two speed option?

 

has anyone acually shown to get better mileage when going to 285/70's?

 

Ok, with my hemi Ram the best that I have ever gotten was 19.8 on a Sunday morning trip from New Jersey to Maine. Very light traffic, cruise control 60-64 mph. 65 and over it drops like a rock. My average in Maine is between 16.5- 17.5 , but towing or horsing around , like beating up Tundras, its pretty bad. I'm hankering for a Cummins bad, though.

 

I remember reading a post about a year and a half ago, that someone went from 245's to 285's on his truck and seen a major fuel improvment and about 400RPM's lower. going from 265's to 285's i wont see that much of a improvment, but i am looking at seeing some. That is why i am waiting until my tires wear out, i only have 7k miles on these.

Maybe MikeyB can give us some hard numbers


In diesel power magazine about 3 months ago, they put the gear splitter on project-x which increased their MPG and also top speed. This is one thing i have in my plans to do also, I wish they would of given some solid info on MPG inprovment with the gear splitter.

 

OMG! I must be doing somethin' wrong, even when I drive like I have sense, I get 16-17 average, with the only mods to engine being an AirRaid intake tube/filter... almost 37K on odo, it's got to be broken in by now, right ?I have been running Amsoil since 6K... and I just 1k ago, put a full set of stock sized Bridgestone tires on (after I ran over something that ripped the left front wide open @75mph on D.C. beltway) my next mods will certainly be a computer upgrade, as I've been embarassed by a couple of Ford Powersmokers, and a Toyoyo... can't be havin that!!

 

compmoto the only thing you're doing wrong is telling the truth. That's what these 4x4 trucks get. I've got a gear splitter and free spin hubs and my empty running hand calcs are always a tad under 19 mpg.

Sevir if you're expecting huge mpg gains from a splitter you'll be dissappointed. From my experience it only benefits you when you're running 75/80 mph on the freeway where it keeps the mileage from dropping off so precipitously. It does a good job of maintaining your mileage at higher speeds. But if you don't run a lot of interstate it's not worth it and even then it will take years to recoup the cost.

 

Running the speed limit gets me 14-17.
At over 11,000 lbs and with lotsa idle time, I have no room to complain.

 

that is the main reason I don't have a 4x4