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How to screw up checking our gas mileage...

fpdsniper

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fpdsniper Enthusiast

fpdsniper

Posted
Posted

Excuse my little rant here, but it annoys the crap out of me when I see people post their gas mileage and can't figure out why other are getting more than them. Yes, at times there could be a mechanical issue, but usually it's driver/owner error. So I decided to post a list of ways that you can screw up checking your mpg's. Here we go:

 

1. Not resetting your trip meter/mileage tracker when checking your mpg's. Your on board computer is constantly averaging your mpg's. To get an accurate number, clear it when you fill up and want to check it. If you don't, you're just getting an overall average regardless of how you drive during this fill up.

 

2. Drive aggressively. Accelerate hard from stops, pass full throttle even when you don't really need to, exceed all posted speed limits, brake at the last minute rather than coast to slow your speed, and do lot's of idling! That'll show that silly computer who's boss!!!

 

3. Start your truck, and let her warm up for a good, long time! Remember, you can actually achieve ZERO miles per gallon if you're really good at this!!!

 

4. Upgrade to larger tires, and forget about adjusting the tire size difference. That requires some math, and using the calculator in your smart phone. Who's got time for that???

 

5. Don't bother with putting a reasonable amount of miles on the truck while checking your gas mileage. 2 miles should do it. Just remember to keep the peddle mashed to the floor during this time. Otherwise, you won't be able to post how terrible your gas mileage is on forums!!

 

 

OK, I'll stop with all the extreme sarcasm. Listen guys, you can't do the things I posted above and get an accurate reading of what your truck is CAPABLE of getting mpg wise! If you do, you are making the conscious decision to impair the ability of your truck to get great mpg's. My truck is capable of a solid 21-22 mpg in 70% highway, 30% in town driving as long as I do my part. I could easily take that down to around 10mpg if I don't do my part, but how could I blame my truck for that? My point is, many don't understand how to get an accurate reading, or how to get the most out of their truck. If you don't, the fault lies with you. Feel free to disagree, but I hope some of you understand what I'm saying here. Rant off..... :)

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Rawyzf Senior Enthusiast

Rawyzf

Posted
Posted

I hand calculate every tank and track it in fuelly. Best way to get an accurate reading.

 

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mikedege Enthusiast

mikedege

Posted
Posted

21mpg in my 1st tank on the 6.2L. Pretty impressive to me!!!

 

Mike

fpdsniper Enthusiast

fpdsniper

Posted
  • Author
Posted

I hand calculate every tank and track it in fuelly. Best way to get an accurate reading.

 

Sent from Tapatalk App - Samsung S6

True, but the on board computer does a great job IF you use it correctly. Many don't.

Rawyzf Senior Enthusiast

Rawyzf

Posted
Posted

True, but the on board computer does a great job IF you use it correctly. Many don't.

On board was .5 off for me most of the time. But, still decent.

 

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2018GMC Senior Enthusiast

2018GMC

Posted
Posted

Nice write up, heavy on the sarcasm lol

hurricanoday Enthusiast

hurricanoday

Posted
Posted

On board was .5 off for me most of the time. But, still decent.

 

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How do you know you are not .5 off most of the time? I find it hard to believe that people can accurately, or at least more than the computer, calculate how much gas has been used and how much is left in the tank when they fill up. I know my truck says 26 gallon tank and I have put more gas than that in before and it was still running.

 

Unless you drive it till it stops and then put exactly 26 gallons in then it isn't completely accurate right?

PMattras Enthusiast

PMattras

Posted
Posted

I do everything noted above (plus) and I only get between 15 to 17 mpg in the New England (CT - not flat) area. I have a regular cab and only a few major options on this truck. I also have a bed cover. Travel very light all the time and have about 15,000 miles. Highways and back roads. I never seen anything over 17 mpg in this area when I checked. I have 3.08 rear end. Use different gas from different gas stations etc.. No towing. Left stock. I don't feel the gas mileage is that great with a 5.3 V-8 period.

 

My summer car 2006 MX-5 six speed manual (167 hp - 4 cyl) gets 34 to 42 mpg in the same area of travel and a lot of fun to drive. Don't see the gas station that often with this vehicle.

tnchevy Senior Enthusiast

tnchevy

Posted
Posted

I live in a very hilly area as well and my 5.3 3.42 geared truck gets 19 to 20 mpg in the summer, 17 to 18 in the winter. I keep my truck in M5 when I am crossing over curvy mountain roads and on the really curvy ones I just knock it down to 4 the gear, truck is not going crazy shifting gears and gets better mpg's. I seriously think that a large portion of the population does not know how to manually calculate their gas mileage.

toro1966 Enthusiast

toro1966

Posted
Posted

I got 22 on my first tank and that was mostly highway. I have averaged 21 and change on my second tank with a mix of highway/city...That' with a 6.2L

Dadof2 Enthusiast

Dadof2

Posted
Posted

I agree how you drive plays the biggest part in your MPG. Mine turned 20K miles yesterday. Bought it Dec '14. It's a CC, 5.3, 3:42 4wd. Per my Onstar app the lifetime MPG is 21. I can easily drive through a tank and make it get 14 or even less.

 

You probably don't want to get stuck behind me though.

CbrownGT Enthusiast

CbrownGT

Posted
Posted

My '14 with a 5.3, 3.42 gears, 2.5 level, and 285/65/18 AT tires gets 17.5-19 driving in hilly western Pennsylvania. I hand calculate it every now and then when I fill up (always account to tire size difference too). I don't baby the throttle or mash on it much. I just drive..how I drive. Depends on traffic, time, and type of road.

 

All I can really say is: you're driving a TRUCK with a V8, if you're worried about MPG's you purchased the wrong vehicle....

Rawyzf Senior Enthusiast

Rawyzf

Posted
Posted

How do you know you are not .5 off most of the time? I find it hard to believe that people can accurately, or at least more than the computer, calculate how much gas has been used and how much is left in the tank when they fill up. I know my truck says 26 gallon tank and I have put more gas than that in before and it was still running.

 

Unless you drive it till it stops and then put exactly 26 gallons in then it isn't completely accurate right?

Hand calculate is way more accurate, it's simple. Reset the trip when you fill up (first click of pump at same station). Drive until you feel the need to fill up again. (First click again). Take those gallons and divide the trip miles, and you have your mpgs. Reset trip and repeat.

 

Gas pumps are very accurate on their output. I know there is a little variable in where the pump shuts off, but if you use the same station, it's best.

 

Sent from Tapatalk App - Samsung S6

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