Why are my MPGs so bad?

Ive seen folks say they are at 16-17 avg. I drive 70% highway/30% city and I am averaging 13 mpg according to the HUD. Ive got a complete intake, cat back exhaust, and run 87. I do not have a lead foot and cant figure out why my mpgs are so bad.

 

13 is not bad at all. I get less than 10 (sometimes around 7). Average mpg is mysterious thing since everyone's driving condition is different. I bet that any of those trucks with 16 average mpg will get less than 10 in my neighborhood under my driving condition.

If you are interested in saving some mpg pennies (not dollars, haha), here are couple of things you could do (from what I could see in your picture).
1. Change out to smaller wheels. For the same overall diameter tires, smaller the wheels, better mpg you will get.
2. Change out your good-looking but heavy BFG AT-KO to something that is p-rated.

Your truck won't look as cool, but, hey, you wanted to save some pennies, right?

 

I average either side of 18 mpg, I do have a lighter truck though (RCSB). My tires are stock 275/55/20 and I run them at just under 40 psi. I've also found a filling station that has non-ethanol gas and I run that exclusively. I have no idea if my tonneau cover helps or not. With all the mountains, driving up and down, I think that it averages out so I don't really factor that in. No leveling kit either.

 

i've got a rock warrior and i've never hit over 15 no matter how hard i've tried. those tires kind of kill it compared to regular street tires

 

Before I changed out to TRD coil covers my indicator showed 13.2. After resetting and driving in town for several hundred miles, it registered 10.1 avg. After tonno and borla swap in it's registering 11.3 I'm driving down to my property Thursday which will be 250 m on freeway each way. I expect it to pop back up to 13 or 14 by the time I get back on the 7th.

 

It's a full size truck with a V8...

 

at best i get 14 and its a truck.

 

I will be very happy if I get 14. Especially at high altitude. 5280 and way up.

 

Im just trying to figure out how people are claiming 16+.

 

I can see that maybe with stock lift and stock Duelers, at low altitude, freeway driving a lot, and 2WD. Need to see pics of mpg avg indicator showing 16+.

 

@zac808

Looks like you live somewhere with a warm climate based off your picture. Do you tend to start the truck and let it idle while cooling off the interior?

In general
Do you allow the engine to idle for extended periods of time?
Do you tow?
You have heavier wheels and tires than what was originally fitted.
Your performance mods aren't going to help.

Have you manually calculated your fuel economy?

Have you taken into account your upsized tires? You are now traveling a further distance than what is being registered if you do not have the hypertech recalibrator.

You can't compare apples to oranges. Other claiming 16 may live in a mild climate with flat land. They may never use AC, tow/haul, cold climate idling to heat cabin...etc

 

Definitely manually calculate mpg. I always do it when I'm driving any long distance.

 

I have the tow package which includes the 4.3 to 1 diff. With my tires and diff gears, 14 would be something to brag about IMO. Hell, when I was getting ten mpg I didn't care, but I'll take anything I can get.

 

You will never get a return on investment for regearing at 33/35s - you'll absolutely love the new powerband! but gas savings wont add up that quickly.

 

If you really think about it we probably don't ever a return on investment for a lot that we do to our trucks. heh heh. If you first approach this fact when starting to add goodies then it will never be an issue. A least that's the way I look at it. More fun, less things to stress over.

 

But were not talking about regearing just to regear, that was a suggestion to solve a problem/increase economy - nothing more. So to regear for the sole purpose of increasing MPG - ROI is null.

Now if we were talking a different scenario I would agree with you.

Edit.
Your right - it will increase MPG. If you dont care how much money it takes to get you a few more then go ahead...at least your MPG will be where you want it - despite how much fuel monies used to get you there.

 

I was actually agreeing with you. I agree that the discussion was not about "re-gearing just to re-gear". I don't recall saying anything about "re-gearing to re-gear". I re-read my post. Nothing about "re-gearing" in my post. It would be foolish to re-gear just to re-gear. Some folks will re-gear UP after moving to 35" and larger tires to regain the ooommpf that's lost like you stated. Nothing to do with MPG or ROI obviously. Chevy offers as low as 3.08:1 diff which gets good mpg but torque band sucks. I was agreeing with you in general terms about expecting to reap a ROI on what is spent on our trucks. Never said to willy nilly spend money carelessly let alone "re-gearing just to re-gear". I am just the opposite. Always looking for the best bang for my buck. I have no expectations on ROI. That was my point. The correct scenario. You are right about apples and oranges. A lot of factors come in to play for sure.

 

As you know, along with many others on this site I had a Tacoma. Went to the Tundra for towing. I can bite the bullet while towung but normal driving is not what I expected.

 

Ditto. Came from TW and needed towing.

 

Diddo x2
Came from a 2008 Access Cab 2.7l 1wd 6 lug

I just wanted a beast of a truck lol towing ended up being a plus

 

My 09 Taco had the 2.7L too. I towed a 17ft trailer with two Ski Doo's all the way back from Anchorage. There were a couple of passes where I could barely stay in third. I have to totally back off with my Tundra.

 

My typical driving is stop and go city driving. My mpg's aren't too great either. Same driving my taco wasn't a lot better, but this truck is an absolute beast, i love it.
I drive it like there is an egg under the pedal too...

 

I try to drive as if there is an egg down there but my fly by wire pedal is so darn sensitive. PITA at times,

 

Since we have an MPG thread, I'll toss out my purely anecdotal experience concerning name-brand gas vs 'cheap' stuff. I used to fill up my Tacoma at Costco whenever I made a run into town, otherwise it was at the local Shell station (only local option). I began to notice that my Costco mileage just didn't seem to be hacking it, so I started closely tracking things.

I ran an experiment with three tanks of gas (all 87 octane) from each source. All three tanks from Shell averaged 16 MPG, while all three tanks from Costco averaged 12 MPG. Even though I was "saving" 6% in dollar-terms at the pump, I was losing my ass to the tune of a 25% drop in fuel economy. I'm 100% Shell now.

Dunno where you buy your go-juice OP and I'm not trying to shift this to a 'gas wars' thread , just plopping my 2-cents on the table for your perusal. Oh, and my Tundra averages 14.4 overall, turning 33's with 90-95% highway miles.

 

Actually, I always use Costco. May be time to try something else.

 

I had a similar experience with Sams Club fuel. Cheaper but "source"?. I try to use the Shell near me most of the time which is 10 to 12 cents higher. I'm going on a road trip in a couple of days for vacation. I expect to see my average go up. Last year round trip to my property was 13 something. That was before tonno, K&N, & Borla swap. I'll have a full tank of shell when I leave. One way is approx 250 miles so I can manually compute my one way mileage when I get there. I'll be on cruise a lot. It will be interesting to see how much this combo will help mpg overall.

 

Certainly worth a tank or two just to see how it tracks. If you don't see improvement, then nothing lost but a couple bucks.

I took a trip into the mountains a few weeks ago, dragging my camp trailer (~7K lbs) behind me. On one particularly steep section of fire road my Ultraguage had me riding at 1.0 MPG--now there's some crappy fuel economy! Good thing I was in 2WD or it would've surely been in the 0.x range!

Not to sound like a commercial for Shell, but I also have one of their fuel cards now. I get an instant drop of 3 cents off the sign price at the pump, plus Shell knocks another 5 cents off at the end of the month on my statement. Paying 8 cents/gallon less than the sign price puts a nice dent in the price difference with the discount stations too.