Insanely Low MPG, Can't Get a Clear Answer, PLEASE HELP

Yeah something makes me think math is still wrong here but everyone has the right idea.

30.6" is the OE tire size (265/70/16)
33" is the new tire size (275/60/20)
Difference is +7.8% increase in circumference so correction factor is about 1.078.
Trip ODO of 196 miles * 1.078 correction = 211.29 corrected miles / 14.4 gallons = 14.67 miles per gallon.

As others have stated first off having a lift will cut mileage. Then your wheels/tires are extremely heavy which will cut mileage. They are also wider (275) which will cut mileage. With your setup, getting ~15mpgs is realistically what I would expect.

Get lighter wheels/tires or pay at the pump.

EDIT: Corrected my math because I can't read. Had to take my shoes off to count.

 

OEM Tire size on a TRD OR is 30.5"



HOWEVER, OP says TRD OR sport, which isn't a thing. Definitely not 26.9" tires, though.

 

You're right, I don't know why TireSize calculator gave me wrong numbers (or I can't read). I'll correct my maths above. That's even worse then.

 

I wish I could get 14 mpg... or 12... maybe even 11?

 

~14mpg is yikes man.. so it's basically 220 miles per tank before you see the yellow light.. and that would be highway mileage right? So city would be even worse.

 

I understand how to do mileage math.

 

I only get around 260 miles per tank. I live in New England so its super hilly. Bone stock I got around 280.

 

So I caught this about the same time you commented. I typo'd one of the numbers I put in the tire size converter. OEM tires are actually 30.6" ... So I started all over with my conversion equation and came out to 14.7/mpg. Trip difference of roughly 15 miles or so. So my MPG sounds about right now, so my only issue I'm still facing revolves around my gas gauge. At 14.4 gal pumped, that's 68% of the 21.1 gal tank. I drove it for around 20 miles after the light came on, which would indicate 4 gal left. Even if I only used 1.5 of the 4 gal, I should've been able to pump 17 or so in.

 

Yeah, I caught this. I had a typo on the size I put in on the converter. I got the same thing you did above when I fixed it.

 

It's yikes, but it's less yikes than the 10 mpg I thought I was getting. It allows me to be a little more patient in getting this Godforsaken lift off of it.

 

Just sell the truck and buy a stock one. Trying to reweld the front crossmember is going to be a headache.

 

Sounds right in my experience for gas fill up. I know they say 21 gallons but when the light goes on its about 15gal.

 

even if you get the lift off itll do like MAYBE .5mpg, its the wheels and tires. Did the previous owner regear it? If youre still having tank size trouble just drop the tank and while youre at it change the fuel pump or not, compare to oem. v6 tacoma 4x4 auto doesnt get great mileage even stock

 

If you haven't fixed your speedometer with the device that fixes it, then your odometer is off, and you cannot rely on your odometer for a fuel economy check. It is likely higher by a mile or two. Use Google Maps "measure distance" from pump to pump to find out how far you actually drove between fillups.

 

I get that 18 mpg comb with 285s, canopy, and a 2 inch lift using scan gauge. But our speed limit is 60mph/100KMH so that makes a big difference.

 

Speed limit - does ur gas pedal not go down a little further?

 

I would try a lighter wheel and tire combo first. Drop bracket is a pain in the ass to reverse.

 

For myself, I've always been right around 17 gallons when the light trips..never replaced the fuel pump for the record

 

Mine also is usually around 15 gal fill up when the light comes on. Occasionally it’ll be an issue with the pump clicking off too soon. My Nissan nv would fit another 2 gallons after clicking and doing a weird gurgling thing. It only got about 6mpg so I’d try to get it full as possible. Not suggested doing that to a Tacoma.

 

You sure that wasn't fuel going into your evap system? lol