Gasser real world fuel economy

rdboyd

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Just got back from a trip from Southern Indiana to North Carolina. Was planning to go to Myrtle Beach, but the lack of gas changed our mind so we spent a weekend in Tennessee instead. Manual transmission Overland with stock wheels and AT tires averaged over 23 mpg for a trip close to 1500 miles. Odometer hit 5000 miles on the trip. This includes driving over some dirt roads through the mountains.





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NachoRuby

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Just got back from a trip from Southern Indiana to North Carolina. Was planning to go to Myrtle Beach, but the lack of gas changed our mind so we spent a weekend in Tennessee instead. Manual transmission Overland with stock wheels and AT tires averaged over 23 mpg for a trip close to 1500 miles. Odometer hit 5000 miles on the trip. This includes driving over some dirt roads through the mountains.
That's great mpg! Hoping my Rubi gets there someday, but it's a bit heavier, plus with the mud tires and being slightly larger in diameter, I don't know.
 
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Toyfrog

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So... Not a datapoint to add to the spreadsheet exactly, but I've been following this and ruminating a bit. Personally, I don't feel great about any vehicle making less than 20mpg. There's no rhyme or reason to it, just kinda makes me feel bad. My diesel Bison obviously beats that, but it's sold and on its way out the door. I never really looked at the fuel economy of any of the gassers until I started considering the Gladiator, and I'm not happy with the 16-17 I'm seeing here.

That said, what has eased my mind considerably in my car buying research is going and looking at the competition. The gas Colorado is the lowest, I think it was the Tacoma or Ridgeline that's the highest (I might not have included the Ridgeline in my search at that point for obvious reasons, but if I did, it was the Ridgeline and the Tacoma falls in with everyone else). The spread is something like 3mpg top to bottom, with all but the outliers at 19mpg EPA rating. So, the Gladiator is smack in the middle AVERAGE for fuel economy by that metric.

Of course, people's mileage is literally varying here, and that seems to come down very clearly to modifications, environment, and driving behavior. I have a good feel for ZR2 fuel economy, coming from that world as I do, and then there's this thread here. So I went and looked at the Tacoma forums (the only other possible, but not really, contender). They're in the same boat. Similarly modified Tacomas are getting MAYBE 1 mpg better on average, but we know if you put a Gladiator and Tacoma modified to the same degree from stock (measured by dollars and effort), the Gladiator will win every time on every metric.

So, that brings us down to the primary factors for mpg being degree of modifications, environment, and driving behavior. To wit, my wife's DD (and mine until the Gladiator comes home) is a manual JKUR. She is not as interested in modifying her Jeep as I am, so modifications have mostly been for usability rather than performance. She runs 33" tires in the winter (calibrated via AEV dumaflache), and is about to replace her factory tires from wear at about 80K on the clock (35s may be in her near future, but it's not my call). Her combined mpg is 21-22 mpg (depending on season), and I tend to beat her by 1-2 mpg when I drive. I went and looked at mpg averages for JKURs, and lo and behold, 16-17mpg. JL to JK EPA rating is +1, I guess for aero improvements, and JL to JT is the same (for aero un-improvements).

Connecting the dots, since the delta from JK to JL is the same/reverse as the delta from JL to JT, I should be looking at a very similar situation. JKUR 31-33 change in tires is about the same as the change from 33-35 on the JTR, so I should be looking at a similar situation there as well. Jeep is one of the few manufacturers whose automatic transmission programming doesn't net better fuel economy than the manual at this point in the game, so that costs me 1 mpg in this analysis (I need the truck for truck things, and the auto is necessary to get those numbers). That should essentially erase the benefits I gain from my driving habits/style relative to my wife's. So... Once we're back to more or less exclusively driving our respective vehicles, we should get about the same mpg, which is above my 20 mpg pain point ASSUMING no engine build QC issues or other unknown unknowns.

I know that's a lot, and it's topic adjacent, but seemed like it might be worth sharing/discussing/getting out there for anyone in a similar situation.
From a guy that has spent the last 27 years in Tacoma’s, even before they were called Tacoma’s. My last one, the one I sold to get my Mojave. 2012 4 door 4x4 auto, 3 inch fox/OME lift, 285/70/17. Averaged about 16-16.5 on the same drive I’m getting with a stock height Mojave with 316/70/17. IMO Toyota is going the wrong way with both of there trucks, that’s why I went with the JT
 

ShadowsPapa

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I've run three different tires now with no other changes - and can tell, as most should already know - tires, tires, tires. Why would anyone who goes beyond the stock Overland 10" wide 32.2" tires even think about decent MPG?
I easily got over 22 mpg with my stock tires. Putting on the Rubicon "take-offs" - the Falken A/T tires at 11.2" wide and 32.7" tall dropped me below 20, usually averaging 18s, sometimes getting to 19.
With the General 10.8" wide 32.2" tires my mpg is up again, but I can see already it won't be 22-23.
Nothing else changed - tires only.
So I went from stock 22-23 mpg, even hitting 24+ when keeping it under 60 on level ground
down to 18 or so with the heavier, bigger Falken tires
And back up to what could settle out at 20 with the General tires (maybe better, dunno, haven't had them but a few days)
So putting tires over 33" tall and/or 11-12" wide with aggressive A/T or M/T tread is going to make your MPG suck.
More weight (to make move AND to stop so more against the brakes, too), more rubber on the highway means more friction, more drag.

And of course a lift will impact MPG - you are lifting your sail higher up into the air. It's going to catch more wind plus - more drag from the wind hitting the fronts of the tires and the steering and suspension and front differential catch more air - more drag. It's why there are air dams, and other ground effects, as well as panels and such smoothing the bottoms of vehicles and blocking wind from beneath the vehicle.
So any lift will impact MPG.

Weight - put that winch, steel bumper, skid plates, whatever, on there and now that engine must pull around all of your additions and accessories besides you and the truck.
The more weight there is, the more HP it takes to pull it, the more your foot lets more air in and the more the electronics have to tune the fuel going in.

Your best mpg should logically come from a stock Overland or stock Sport.
Anything else will be less and ANY change you make that increases its face in the wind, total vehicle weight (tires, bumpers, skid plates, bed mat) or that adds rubber to the highway (bigger, wider, heavier tires) will decrease mpg.

Manual vs. automatic - hard to directly compare because you have human psychology involved - the type of driver that would buy and drive a stick compared to automatic - hard to do a direct comparison unless the exact same driver drove both in the same ways.
 

Slojo

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What "Generals" are you running?
 

Higher_Ground

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I kind of want to put together an XY scatter plot for speed vs. instant MPG.

I feel like I can find a sweet spot traveling around 40-50 mph where the instant MPG reading is 25+ but it's not often you find yourself cruising at that speed. Push it to 60-70 and my MPG goes back down to 16-18. Under 35 mph is mostly accelerating and not maintaining a steady speed.

Would make for an interesting graph at least.
 

Tufelhundin

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Well crap… I got the luck of the draw… I seemed screwed from the beginning for I saw 17mpg stock.😂


I swear that extra they charge for stingray must be a dollar we pound . 🤔😂
 

midironman

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16 highway, 14 city. JTR with tow pkg and AT. 2" lift, 35's. I live at 1400 ft above sea-level and drive in hilly areas. I drive it to get where I'm going at a good pace, but nothing excessive.
 

48 Willys truck

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2021 Sport base model 6 speed. Did not drive it over the winter.


DateOdometerGalMPG
11/2/20208
11/17/20201689.34917.11
5/2/202131911.78912.81
5/18/20215179.16221.61
5/23/20217479.95923.09
 

49Gramps

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Bone stock, 3.6, automatic, with 600 miles on it we went to Florida. 3237 mile trip, mostly highway, lot of stop & go traffic around Miami and DC, did some 3-5 mph sightseeing (Loop Road, Big Cypress Preserve). A/C on constantly, rarely used the start/stop. Average for the trip was 24.6 mpg!
 

Caspien

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21 JTR, 33" Factory Mud Tires, nothing else special (yet). Hand calc and dash computer are close, but not quite the same on calc. Dash reports 18.2, hand, I calc in at 18.7.

2500 miles so far... 100% mix of town, city, and highway/back roads.

Prior to 800 miles, I was getting about 15mpg...one of the techs, at the dealership, when we bought it actually pointed out that his took about 800-1000 miles to 'break in', and start getting better performance. He wasn't wrong...but as to 'why?', I have no idea :)



~ Casp
 

cecaa850

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Trip to the TX hill country this weekend. About an hour and a half of this was in a torrential downpour.

20210601_072631.jpg
 

HuskerMojave

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How the hell?
I'm starting to feel like something is wrong with mine lol
Just did a trip from Scottsbluff Ne to Breckenridge Co last night had a 16 avg. and I was at that before heading up the mountain. Bone stock Mojave with MTs and 1400 miles.
 

Berserker556

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Just did a trip from Scottsbluff Ne to Breckenridge Co last night had a 16 avg. and I was at that before heading up the mountain. Bone stock Mojave with MTs and 1400 miles.
I drove from ky to Indiana best I got was 22 lots of hills though.
 

JTWAVE

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Completely stock Mojave with a/t's, drive slower than grandpa, easy acceleration, mostly highway but some city. I'll turn off the climate control just to make sure the start stop kicks on. My best "average" 16.6, current 15.4. I have no idea why I dropped 1 mpg average overnight either, just got in the next day and it had changed.
I'm still under 2k miles though and it was only getting 14.x.
Screenshot_20210418-175357_FillUp.jpg
2021 Mojave - stock lift and stock 33's and 4.10 rear. 16-17 mpg in the city. 14-15 mpg on the freeway where its 75mpg on the freeway. Anything over 70 mph puts my rpm over 3000 and kills my gas mileage.
 

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