Low gas Mileage

Ghostknight41 · March 2, 2023

Hey everyone, so I got a question, I have a 2019 silverado 5.3l v8 new body style, I randomly noticed when I filled my truck up it said I was only getting 267miles to the take, and getting 9.2 mpg, it's a 23 or 24gal tank, it runs fine I'm up on the maintenance, so I ran threw the tank and filled up again and almost the same issue. I've researched it a bit and gm said it's supposed to be around 403miles a tank, I've seen other guys have a half tank and they have 215 to 230miles left and getting between 18-23 mpg. Can my short drive to work cause this? I live 7 miles from work so 14miles a day all highway. Today I'm at just before half tank and it says I have 143 miles left. Anything to try or look into would be great.

jaxcam02 · March 3, 2023

How exactly are you calculating mileage? Are you just assuming you know the tank size and assuming you ran the full tank empty?

Ghostknight41 · March 3, 2023

The tank size I used the info from my vin to figure out the size, and I'm going by the screen that tells me all my mpg and miles to empty. And yeah I've also ran it to empty then filled it to get the average size.

newdude · March 3, 2023

"Your mileage may vary"

Short trips kill mileage. If you have lots of stop and go on your commute, that kills mileage. If you remote start for long periods of time, that eats up fuel.

Tank is 24 gallons, that is correct. Have you ever hand calculated a tank? So fill the tank, reset one of your trip meters, run through the tank. When you fill it up again, take total miles driven divided by the fuel added during fill up.

So say you went 280mi on the tank. Took 21 gallons. That would be 13.3mpg hand calculated. At your 267mi, was that to the fuel light being on? Lets assume so, that leaves about 2 gallons in the tank at best. 267mi divide by 22 gal that's 12.1mpg.

Ghostknight41 · March 3, 2023

Ok, cool I'll try what u said, n do the math, I figured something with the short trips, I have like 2 months left on the factory warranty, before the other warranty kicks in, if there was something wrong I wanted gm to fix it, because I had a issue before with the sensor that tells u how full the tank was. N I would fill it, it would say I only 3/4 of a tank, they flashed the sensor n it seemed fine, it just made me wonder.

KARNUT · March 3, 2023

I get about 5 mpg difference in my wife’s car in town than she does. To the good. I anticipate lights take off smoothly still aggressively. And limit idle time. Look at a plug it’ll tell you if it’s over fueling.

jaxcam02 · March 3, 2023

I would recommend you download the smartphone app "Acar" I have been tracking every fuel up I have ever made on all my vehicles since 2009. It calculates your actual mileage by just inputting your odometer reading, gallons pumped and total cost of fuel every time you fill up. There are loads of other parameters that it will calculate as well.

SteveP45 · March 3, 2023

Do you have a heavy foot?

My 2019 has a little over 54K miles on it.

When I fill my tank, I am getting an estimated 457 mile range to empty. Normally get 18 to 21+ mpg in daily driving. The best mileage it calculated and it was on Interstate highway with a tail wind was 29.1.... before that it was 26 mpg.

When towing a double axle trailer loaded down with several pallets of wood and 3 passengers besides myself, the mileage is 15 mpg even on interstate.

Let the transmission shift and do the work to get you up to speed. Sweet spot for excellent mileage on the 5.3 is under 2,000 rpm... really it is at about 1,500 to 1,800 rpm.

The terrain you drive has a lot to do with it.

I use only full synthetic oil (0w-20) and full synthetic oil filter and I am always on top of changing the oil & filter before it needs to be done. Do not wait for the oil life monitor to tell you to change it.

Yader · October 19

I had the same issue. With my Chevrolet Silverado 1500 2024.

i went one day from doing 22 mpg and the next day 10mpg without towing anything and my range of miles to full tank was 466 and the next time I filled up it gave me 276 gallon to full tank. It been like 4 days and it have not change. The dealer says it nothing wrong. I don’t trust them. I am not an aggressive driver and was not driving more then 65 miles. I will go to dealership next time and have them show me another vehicle line my and see how much the full tank will show in miles I will guaranteed it will be around 460. I was doing 9 MPG heading to Miami driving 65 miles.