I'm on a mission to improve the mpg in my truck. I commute about 65 miles a day now, and I have a great route for VERY consistent mpg checks. It is more about the results than about saving a ton of money, but every little bit helps! Cruise control at 65mph, mileage checked with a GPS, 6th gear at 1650rpm...
My best results so far are 17.05mpg and 17.35mpg using Smarty level 0 (1/2 power) and Smarty level 1 (lots of timing) without the EZ plugged in. Now remember, I have a 4.5" lift and 37" tires, so wind drag sucks! Not to mention the mach3 injectors can dump some fuel.
I am going to add synthetics to the diffs in the next month or so and I'll test synthetic in the engine at the next oil change. Are there any pros or cons to running synthetic ATF in the transfer case?
Besides lubes, I may add a cab height camper shell or a tonneau cover to hide my bed contents (at least that's what the wife believes!)
Suggestions or combos to try are welcome!

 

you're running 37" toyo mud terrain tires and are wondering how to bring fuel mileage up?? You may be lugging the motor a bit in 6th at 1650rpm, maybe try 60mph in 5th?
Maybe thinner tires on your stock rims (if you still have them) for the commute? 255/85 R16's are almost 34 inches tall...and probably wouldn't look too bad with the lift.

 

I'm not trying to get super mileage overall, I'm trying to get the most I can with the combo I'm running. I LOVE my truck, it took me 6 years to get it like I wanted it! It is more of a research project since I have a consistent route to run. I will get a commuter car in a month or two so I don't have to pile the empty miles on the truck.
I got 21-22 mpg when the truck was stock, so I think 17ish is pretty good with 37s and 1000 lbs of torque! I'm shooting for 20 with synthetics and a tonneau...

 

TC uses atf+4 same as the tranny and its already synthetic, you could try running higher tire pressure, maybe switch the diffs to a better gear oil (amsoil to name one) I find I get better mileage with my Juice/attitude on level 5 vice stock or level 1

 

I really hope you can document a milage improvement with synthetic. Keep us posted unless you are associated with glorious Amsoil in any way.

 

That's funny! I always try to add a little caveat at the bottom of my posts that I am not associated with any shop or company...
Last week I adjusted my toe in from about 3/4" toe in to 1/8" toe in. Pretty close to zero with 37" tires. On the same settings (down to tire pressure) I gained .6 mpg!
My two best combos to date are:
Smarty level 0 (1/2 power) without the EZ...........17.59 mpg
Smarty level 1 (lots o' timing) without the EZ........17.84 mpg

Driving manners are very nice on both settings, cruise control doesn't surge hardly at all.

 

Im using Amsoil on the truck everywhere and ATF+4 in the trans and transfer case severe gear 75-140 in front and back Diff's

 

why did you go with 75-140 front and rear? seems a bit overkill, maybe a bit of drag that isn't necessary.
I have nothing against Amsoil, I just don't sell it! I definitely have no problem with it, just don't want this to be construed as a sales pitch for them.

 

How's the truck tracking down the highway with the toe adjustment?
Wonder if this is enough to affect the mileage?

Have you tried any fuel additives of any type? (2-stroke, cetane boost, snake oil, moon shine....)

Do you buy fuel from the same supplier, or do you just pull in to the closest pump?

 

Tracking is great, I will also add a bit more caster after I do some mileage checks. That was really the only change, except maybe some weather stuff...
I have used 2-stroke or power service in the past, but no additives in these tests. I have made a point of using the same station and the same pump for fueling, even filling the tank til the pump stops, shake the bejesus out of the truck to vent a bit (me and the tank), wait a few seconds for the bubbles to subside and fill until the fuel is to the top of the neck. I know I can get between 1.5 to 3 gallons of fuel after it clicks off usually!

 

I've used synthetics in the transfer case since the truck had 15K miles. It does nothing for mileage, except in cold weather - where the synthetic eliminates the need to "unthicken" in the first few miles of driving.

However, I've been told that the properties of synthetics cushion the TC chain better, dampening out harmonics and keeping the chain from stretching, particularly in warm weather while towing. I have no proof of this other than the fact that, as of 77K miles, the chain had not stretched at all when I pulled the back plate off to replace a leaking seal.

btw, I used 75w-140 synthetic in the rear differential and 75w-90 in the front differential - the thicker oil for 2wd towing in summer, and the thinner oil because in 99% of the driving I/we do, we're just pushing the front diff down the road.