Look at VIN tag drivers B pillar:
If a limited 16" wheels locker "AO4A" designation, 4.30's
Non limited 16" wheels locker "AO3A" designation, 4.10's
Toyota varied some on gearing with different sub models,
Sounds as you have 4.10's from how you describe performance and engine condition.

I wish I got 16mpg

I'm not sure 4.30's could even turn 33's without difficulty, that is why some run 5.29's.

I ran 4.30s Woth 33s for a long time and it was totally fine. I averaged 15 mpg doing 75. Ocassionally got 18 to 20 on longer trips. It was never fast but totally acceptable.

Last fall I regeared to 5.29s before buying 35s. I had tons of torque but was spinning 3000 rpm at 70. So not really something I'd want to do everyday and for 33s with an auto 4.88 would be ideal imo.

Now my current state, 35s and 5.29s, the truck is stupidly slow. I go 65 everywhere. Average 13mpg when doing 90% highway and can barely hold 4th gear on anything but flat ground. To the op your numbers really don't seem far off. Maybe a little short on power but these trucks have always been slow af. All I gotta say is there's a reason I bought a supercharger that's awaiting install lol

@gamefreakgc , look at my other post. 4.30's did fine around town OD off, highway on. For a more DD trail rig 4.56's work really good with 33's, I know not much difference 4.30 4.56 to me it keeps rpm's in sweet spot power and mpg's.
34" tire 4.88's, 35" 5.29's not a fan of putting too much gear in since I have to drive 5-6 hr to get to where I would need it. Know what I mean.

Welp great new: Rear o2 sensor failed after 2k miles. New one incoming and I'm hoping mpg improves. Been avg 16.5 highway @70 and 14.5 City.

The tires you are running, are they E rated? I'm running the 255 km2 E rated and they are considerable heavier than stock form. I lost a 1-2 mpg with those tires and loss of power trying to get them moving. I experience some of the same things as you and I'm supercharged and running 4.88 gears. These runners just dont have the power to tow much of anything well. I'm resorting to more boost, 7th injector and tuning it. Small hills aren't much of a problem, but really steep ones just kills any speed for me. Everything you describe seems pretty normal. I'm lucky if I get 16 on the highway.

As others have said, the bigger tires (and more importantly, heavier) will absolutely kill the power. Add that to reducing what little aerodynamics by lifting it as well as a 20+ year old 240+k mile ending and you will have a pig.


Just sort of skimmed the responses, so not sure if anyone has mentioned it, but putting 91 into a normally aspirated 3.4l engine is a complete waste of money.