tires, lifts and other common mods aeffect on mileage

Ive asked in particular threads but rarely got any reply. So use this thread to state what you did to your truck, and what it did to your mileage. I'll check back frequently and put it into a google spreadsheet that i'll share once it has some data.

being exact isn't a big deal, but being honest is.

Lifts, tires, camper shell/tonneau, gearing, tuning, intake, exhaust, truck nuts...

 

nothing changed mine much including E tires and a tonneau, but getting the OV tune on my MT did indeed get me 1-2 added mpg on top of a big whack of torque. I'm not a mileage guy, I'd rather drive the shit out of her, but that's nice I'll take it!

 

I’d be curious to see the spreadsheet when done. I imagine the single biggest variable will be tire size.

 

There are many variables that are hard to value. I think it is safe to say when I added my shell, and then went +1 on tires I didn't really change my mpg at all. Throughout the years I've read many threads on intakes that they don't make a consistent difference on our trucks. Exhausts... minimal.

I think a lift along with a +2 or +3 tires, as well as gearing, would be the things that change the mpg.

The spreadsheet isn't that useful because of the unknown variables of temperature, wind, fuel grade, and other non-declared variances.

 

Mine weighs 6200 pounds. Has 37’s with 4.88’s. Around 2.5” lift. Gets 10.7-11.2 mpg using 91 octane. Only extra drag is a kc light bar. Has a rtt but’s below the cab.

Really cost effective. I’m glad I live in a state with cheap gas.

 

Better than nothing.

 

33" nittos with 32 psi, 3" OME lift with Dakars, winch, US Offroad winch bumper, Pelfeybilt aluminum skidplate, Odyssey group 31 battery, rock sliders, Prinsu roof rack, Bestop Supertop with highlift jack in the back.

Averaging a little over 12.5 mpg combined city and light highway.

 

The patterns I am looking for, more or less are specific items per category.... Tire "A" of a certain size, a specific camper top rather than camper tops in general. Im hoping to find the sore thumbs per component if you get what I'm after. Im not looking for stuff that will hypermile a truck either, I'm looking for the things that rob it of it's given energy. Unknown variables be damned a pile of data could show what some potential bad apples are given a person did X to their truck and noticed Y change and same is true for some one else, some where else with the same out come.

 

The problem is, bigger tires mean the mpg scale is off. I was getting 21-22mpg before I upped size to 235/85/16, then I dropped to 18-19. That is a diameter increase of 31.73/30.47 = 4.135%.

That equates to a 2mpg drop, factoring in mpg change due to the tire rotation. Funny thing is, I went down in tire width. I honestly didn't expect to drop any mpg since I'm only an extra 1" off the ground. It may be cold weather factoring into it too.

I have an ARE V Series camper top with a roof rack, and full armor underneath (bumper, ifs skid, mid skid, tcase skid, gas tank skid, and removed the aerodynamic front skirt -- all of that is factor into the initial mpg). No lift yet, I have a Fox 2.5 setup that's been waiting in my garage forever.


It's amazing how driver and scenario plays into the equation. I've always driven fairly slow and don't use my brakes often as a result, so I usually get better gas mileage than most folks.

 

Not really... If you read the forum, you come to the conclusion that I mentioned. Temperature, Altitude, Wind Speed, Fuel Grade, Point A to Point B measurements and a few other things play significantly into mpg.

 

- one air dam.

 

The whole truck is an air dam!

 

I had a hummer before this. Everything is a gas sipper at this point

 

Biggest variable is driver. Next is environment. While I applaud your effort, nothing is going to be right because of the two above conditions. Shoot, I can put two drivers in identical vehicles and have them drive an identical course in identical conditions and you will get a 10% difference. Seriously.

Rule of thumbs:
1. Any mod that adds weight or changes air flow is a penalty. From tenths to several mpgs.
2. Larger diameter tires are a penalty and gearing won' get it back. Bigger you go, worse it is. Expect 1-3 mpg penalty
3. The rougher the tread, the more rolling resistance you have. Same for wider tire. Expect a tenth for mild AT tire to a few mpg for heavy mud tire.
4. Roof racks, tents, bumpers, skids, and sliders are all penalties. A tenth for sliders and a few mpg for a roof top tent.

Now, with that said, if you do everything, skidsroofracktentslidersbigtireswidetiresbumperswinch you will probably only halve your stock truck mpg.
You have to remember, some of these guys use their instant mpg screen as a true indicator.

Bottom line: If you had everyone figuring their efficiency the Same, over 10K miles, with equal participants at 10K ft and sea level and in between, in both winter and summer, with the same driving habits as far as highway and city, then you would get decent data points. That ain't gonna happen though. Sorry man, the laws of physics are a bitch.

 

Good lord, I've seen fullsize trucks with 37s that get better gas mileage than some Tacomas. Once you go past 265 mileage is out the door.