I know the gas mileage sucks but seriously?

My fuel gauge died (again) and I'm honestly just being lazy because dropping the tank is going to eat up another weekend. I've just been using the trip odometer and filling up every 200 miles or so and not really paying attention to how much. Decided to fill up today and did the math - 10.68 MPG! I just did the whole water pump/timing belt thing and new plugs while I was in there just because. Is that as ridiculous as I think it is? Yes I have a 3" lift and 33s so the speedo is slightly off and I'm pushing more rubber but really? Any thoughts?

 

Are you running 10% ethenol?
To me better off running real gas, as mileage on ethanol is terrible. In many of my vehicles I’ve lost as much as 4-6mpg on ethanol vs 87 octane straight gas, but all my vehicles are older.

I’m running 32.5’s and almost level with new springs, and I been averaging around 17mpg on general driving and 11 mpg off road, since raising the front but I’m running Michelins.
Maybe a fuel system clean is needed.
I’ve ran ATSchemicals 505crf fuel system treatment through mine, and did improve mpg some.
When I first started driving it after getting it think I was getting 14-15mpg since doing everything it’s settled around the 17mpg mentioned, best being close to 20mpg on long highway trip.

Maybe someone else will chime in on lifted ones.

 

Thanks - off to shop for fuel system cleaner. I typically fill up a Costco so yeah most likely ethanol. Haven't bothered to check the %.

 

How old are you? Fuel milage is related to driving style. City or rural? Loud pipes?

 

Get some good injector cleaner.
A lot will depend on driving style and all vehicles are little different. Even with hard 150 mile driving over the mountains, slowing down, speeding up, and 85mph keeping up with EMS I got just a little over 16 mpg. I did have to get some crappy gas before coming back, and I think I only got around 15 with lot easier driving, on turnpike.
I’ve seen damage ethanol can cause, too when it goes, bad so won’t use it unless have to (it’s hygroscopic, acidic, only has a 100 day life if stored in sealed low humidity system etc) so unless vehicle is driven to keep fresh gas its nothing but trouble.

 

Stop doing that. Don't buy at costco, sams or walmart

 

OP,

You driving stop and go or long distances? How fast do you go? Do you try to time your passing so as to roll through a green light or do you race to the red light so you can go hard on the brakes?

I am almost always pulling a trailer and my area of WV is nearly all up hill and down dale. About 8 - 10 mpg pulling the 2-axle trailer (4,000 pound load) and 10 - 12 pulling the single axle (about 2000 ish pound load).* *The weight sticker wore off so I don't know how much that trailer itself weighs. Generally have about 850 pounds load on it when we take it out...

18.85 mpg the one long distance trip I took without trailer, nearly all interstate miles.

I think she gets around 15 mpg in town, no trailer.

I limit myself to 55 mph on the interstate and I do my best to roll through a green light, never "racing to a red light" since well, that's kinda dumb. It takes more fuel to get an object moving than it does to keep it moving---physics.

I was just thinking today...."I wonder how old the spark plugs are".....

 

Or EZ-Mart if in south central states.
I don't know if it's gas or what, but the 2018 GMC company truck is on its 3rd or 4Th fuel pump at 116,000 miles, and it usually gets ez mart gas cause the want the cheapest gas in it.

 

I can't tell you how many cars I've dealt with at work with carbon build up on the valves from inferior gasolines. Not all gasolines are created equal. Cheaper is not better. I have a car right now that is in need of injectors because after doing a carbon cleaning the deposits clogged the injectors.

 

1,000% correct!!
I saw same back when I worked as mechanic and cylinder head machinist?

 

Sams and Walmart I understand, but Costco is TopTier. It should have a good additive/detergent package like the majors (Chevron, Texaco, Exxon, etc). And they sell a lot of it.

 

I get 12 best of times, 7-8 towing. Is what it is. No lift, but oversized tires, and ladder rack.

 

I've seen 19 MPG on the freeway on road trips, and around 12-13 MPG when I drive exclusively in town. You probably also got closer to 11-12 MPG when mileage is corrected for your tires.

 

1uzfe non vvt SC400, I fill it up at Shell stations, most are close to 100% pure gas. If I fill it up at Costco I get alot of issues from stalling to that infamous sulfer smell from the exhaust and horrible gas mileage.

 

How old are your O2 sensors OP?

 

A lift kit, 20 year old V8 and load range E big tires. You are going to be spending a lot on fuel.

 

https://youtu.be/GCPvmZrOK7I?si=j4YRWIMMjZ5dnCbY

My truck cap stole at least 2 mpg, and half of that is because i think my exhaust sounds better.

 

I don't baby it, but I don't lead foot it either. Rarely if ever go past 70. Haven't taken it on a road trip yet, so pretty much all miles are around Houston, city miles with some city freeways (at rush hour). That's if I go into the office, which I rarely do.

Stock 16" wheels, 2WD, usually Shell gas as that's the first gas station I get to in the AM. According to my records, 14.5mpg average. I'm pretty sure if I really cared, I could get it up to a little over 15, maybe even have a tank approaching 16 around town, again if I really cared for the whole tank full and was on the city freeways at the right time of day to make the most of the 60mph. But I don't.

 

Lol, they were terrible in gas mileage when new. Toyota has the Prius and Corolla to boost corporate mileage numbers. Which is good, saved the V8 from cylinder deactivation and 20-speed transmissions.

 

Interesting take....one that doesn't get enough attention.

 

FYI costco gas is chevron as they get it from their refinery, at least in California

 

I don't bother tracking mileage, I just calculate that I will average 15 mpg and plan accordingly.

 

After 300k miles I get the same MPG as new. High 14s if only around town. 16-17 mix. 18+ highway only. I drive easy. I'm sure I could lower MPG if I accelerated faster from stop lights and drove 85 on the highway. I've also got the stock wheels standard size tires.

 

We use Sam's, Walmart and local grocery when at home. When out of town we use whatever fuel station is convenient at the time. Regular unleaded for the Tundra and Sienna. The Lexus RX350 uses higher octane unleaded though I don't think it makes any difference but the wife likes to think so.

 

When calculating mileage, you have to factor in tire diameter. https://www.calculator.net/tire-size-calculator.html
You have to know the size of the tires it came with. Some had 245/70R16 and I think some had 245/75R16.
On long stretches of interstate with mile markers I verify my calculations.
Mine are not lifted, 4x4 with toppers with 6 ply 265/75R16's I get about 15 MPG overall, 17 highway.
I think mileage on these FGT's kinda suck. I had a 1990 2WD Suburban with a 350 and throttle body injection and it got 18 on the highway. It seems like a 16 year newer Toyota with a much smaller V8 and multiport injection would do better. I don't get it.

 

Ground clearance and gearing. Also tuned for reliability, not maximum output.

 

Before I lifted mine, put big meats on it, added a topper with rack and a xtra lights and shit, I got 21mpg once on a trip from Modesto to Napa valley and back. Lucky to get 15mpg now.

 

I've only been around for a little over a year and these mileage threads have popped up a few times. Always popular.

These trucks seem to be all over the place. People with almost exact setups get very different mileage. I don't drive like a grandpa but I drive conservatively, and I usually get 15.something mpg on the highway (driving 70-80mph). I get about 12mpg towing. I once got nearly 17mpg highway, when I experimented with a couple tanks of ethanol-free.

I have 240,000 miles, 255 70 16 (right between the two sizes available stock) tires that are pretty light, and very small lift (around 1"). I didn't see any change in gas mileage when I put on the topper, or the lift. Spark plugs are less than 100,000 miles old, MAF and throttle body have been cleaned, passenger 02 sensors replaced, pvc replaced. Seems like most people here get 12-15mpg, with some outliers claiming 17+ with occasional 20mpg...I believe them, but I see no scenario where my truck could get anywhere near 20mpg.

 

My favorite feature is... the price!