Yea thats my biggest argument for my buddy (the shear amount of ppl that get better mpg with obvious gas gussleing (sp) mods, i have 30 inch tires, no lift, stock gearing) he thinks its driver, i think its mechanical.

Over the weekend i did some testing and found out that my TPS is bad https://www.yotatech.com/forums/f116/busted-tps-187521/ and I will be replacing it when i find a cheap working unit.

 

Is the 16 corrected? Cuz if not, you're actually getting more like 19.7.

 

Tire pressure is the biggest factor for mileage in my truck.

 

What do you mean by "corrected"? Seems like 26-27mpg is pretty high, if not a record. I'm thinking your "corrected" calculations are a bit off. I could see if you had a 2wd and stock sized tires, but a 4wd with 33's, dual cases, probably other weight added to the truck....I don't see how that could be possible.

 

Isaac drives like a grandma, though. SERIOUSLY. He may shift at high RPM, but he ain't exactly snapping the tach needle off getting there.

 

Pumped my tires up from 32 to 42 all around when i filled up today, that may skew the results but w/e im just looking for the cure to my MPG blues

 

A tiff? Really!

 

One, not a record. Lots of folk running that.

The calcs are easy.

My stock sized tire, according to my door jamb is a 225/75R15

That is a diameter of 28.3 inches.

Which is what my speedo gear is calibrated to, and, by extension, my odometer.

So, my "return to stock ratio" would be 33/28.3*4.10, which is equal to 4.78

Divide that by 4.88, and you get .979, or .98.

So, I take the difference in my ODO reading from one fill up to the next. I then multiply that by .98

Then I do the regular MPG calcs.

Works pretty well. Essentially I get worse mileage after my correction.

 

That calculation assumes your speedo was correct to start with, which has not been the case in my experience comparing the speedo to the GPS.

 

i find that most people are liars when it comes to gas mileage...

 

True.

However, its as good as it gets.

I'm just using the exact same method as I did when the truck was stock.

Most figure the MPGS based off of ODO readings and gas filled. Its as good a standard as any.

I should add that one of the reasons my MPG's are quite good is that I have a brand new motor as of 30k ago. That is likely a big difference, though others have seen just as good on older motors.

My old timing chain slipped a tooth, and while the motor was just fine, I had the coin and put in a brand new long block.

 

I like to call it "very optimistic". I had a guy recently tell me he got 35mpg in his 94 Toyota 3.0. I'm thinking his calculator is off quite a bit.

 

My gas mileage sucks, and I don't lie about it. I'm getting about 13.5-13 MPG on my 4runner 3.0.

 

I think the last time I checked I was getting about 17 MPG with my 5spd pickup 22re 268 cam and 31's on stock gears. From what I have been reading that's about right. PSI is about 40 and I don't tach quick and shift between 2,500-3,500 usually. If she is starting to bog with 1/2 peddle I grab a lower gear and she tach's higher but I'm using less peddle=less fuel.

My 4Runner has some issues the 3.0 auto and 33,s stock gears got about 10 MPG but that was about the same with the stock 31's too. This old girl needs some help.

Once I get both tuned a bit better (Especially the 4Runner) I'm thinking they both will get about 15-18 mixed driving which is all I do. State roads 45-55 and little highway 55-65 usually no faster with these 2.

 

Hey, I'm not saying my method is perfect. If you feel there is a better way, I'm all ears. I'm only posting what I calculate and record in my log book at fill ups.

 

Nah, it's just those aren't realistic calculations IMO considering you've added quite a bit of weight to the vehicle and you're coming up with somewhere around 7-10mpg more than the EPA rating of that truck. I would have to ask myself if my calculations might be a bit off if it were me. I've owned 2 different 2wd 22r pickups and have never seen gas mileage near that high(although mine were carb'd models). I never pay much attention to what people claim to be getting for mileage anyways. Some people like to fool themselves into thinking they're getting better mpg than they really are.

 

Well, what do you suggest?

I take the mileage off my odometer and correct for the mismatched tires and gears.

I then divide that number by the number of gallons I put in to fill up. I don't use numbers if I don't fill up completely from one tank to the next.

Seems to me that, if I go a certain number of miles, and use a certain number of gallons, and I divide those two numbers, I will get as good an approximation of the MPG's as anyone.

Weight has nothing to do with the calcs, not sure why that would matter in calculations. The weight would just drag the mileage numbers down.

For example.

Last two fill ups.

2nd to last, My odo reading was 295, 497. Previous fill up was 295, 260. I put in 10.5 gallons, which literally had gas coming out of my filler neck (new set up isn't quite perfect).

So, you take 295, 497 and subtract 295, 260, and get 237 miles. I then multiply by .98 to correct for my tire gear mismatch, which comes to 232.26. I then divide by my 10.5 gallons to get, 22.12 miles per gallon. That tank was mostly city driving, with a few short 55mph sections thrown in.

My last tank was a bit more of a hwy/city mix

previous ODO reading was 265, 497. New reading was 295, 846. I put in 14.6 gallons.

I do the subtraction and get 349 miles. I multiply by .98 again, and get 342.02. Divide by 14.6 gallons, again, coming out the filler neck, and get 23.4 miles per gallon.

If you feel that you have got better math, by all means, share it. I don't estimate anything, and have confirmed with a GPS that my Speedo is 2% off.

I do have several 14 mpgs recorded, which are from wheeling tanks. In low range, the truck barely gets above 15. In the winter my numbers are more in the 19-20 range.

What exactly is the EPA rating on these trucks, as I never saw that number? Truck was purchased in 1988 used, with 7k miles. No EPA sticker on the rig.

 

The only thing I'm saying is I wouldn't worry abbout the .98 factor. Everyone's stock speedo is off by 2% -5%.

 

Well, either way, I fail to see the over-optimism. It is what it is.

 

lol ok dude. I believe you. I get 45mpg in my 93 4Runner so 27mpg in an 88 truck is reasonable.