Does 15mpg sound normal to you? 2011 5.3l

hot37shot · February 6, 2016

I'm noticing my mpg both city and around town getting worse and worse. It runs just fine, maintained to a top! The only thing is I have 275r60 all terrains on the stock chrome 20s with a level kit. This thing did get 20 on the highway when new

Thanks gents

Shawn

Brandon Shane · February 6, 2016

Depending on what size tires your truck came with stock may be effecting your MPG. If it came with 17s and your now on 20s that is more weight to get moving. Leveling kits have also been known to decrease mileage. The stock stance is designed with aerodynamics in mind. Leveling out the stance will cause more wind drag and thus reduce your MPG as well. Truck may look better but your sacrificing gas milage.

Daryl LBZ · February 6, 2016

How many miles are on it? May need a tune up.

Explorer · February 6, 2016

Did you have the speedometer recalibrated with wheel/tire change? This could be messing up your calculations.

intheburbs · February 7, 2016

Well, let me put it this way....I just got home from a 300-mile trip with my 3/4-ton Burb. 6.0 with 3.73 gears, 6500-lb curb weight, and my family of 5 adds ~900 lbs more. I cruised mostly between 80-85, and I averaged 14.8.

Tires can and do have a big impact on mileage, but if you're noticing a gradual drop, I'd say something is wrong.

hot37shot · February 8, 2016

no this thing came with stock 20s. i figured it was the tires, but they are only a tad bigger!? Nope I have not reprogramed the computer and the truck is maintained well. only thing i have not done yet are the plugs, bc it only has 70k on. is it worth paying to have the tire size changes in the computer? i guess they can check for any faults like trans slippage...

Brandon Shane · February 9, 2016

If you have not had it reprogrammed to the new tire size the mileage reading your getting is inaccurate. Larger tires will slow down the revolutions per mile. The computer uses this number to calculate when a mile has been driven. You are probably actually driving further than what your tripometer states and thus an inaccurate calculation for miles per gallon.

Bad Bowtie2 · February 10, 2016

What about fuel treatment?

I add a can of Sea Foam every 6K during my oil changes.

Big Whiskey · February 12, 2016

My average has been right around 15 mpg this winter. Last winter was the same. In the summer I can squeeze 16-16.5 out of it. Tires are one size bigger than stock, front is lifted 2", and speedometer hasn't been corrected.

NEFisher11 · February 12, 2016

I also average around 15 during the winter and about 16 to 16.5 during the summer. Truck is stock no level or aggressive tires.

hot37shot · February 13, 2016

That's solid info and sounds like I am spot on for mpg. I'll keep maintaining the truck to a top including using injector cleaner every 5k.

Thanks for the info !

bgbdwlf2500 · February 18, 2016

Mine is a 2010 that I just bought. Has a leveling kit and someone took off the stock 20s and put 18s on it with 33.5" michelin tires so it has bigger tires but they're more road tires than mud tires. Truck is averaging 14.8 with the 3.08 gears. My guess is because it struggles trying to turn the bigger tires stop light to stop light