Might Help MPG'S

[Jeeperjamie]

Noticed over the past few weeks that my MPGs have went up some since I removed the Wheels spacers a few weeks ago from my jeep. Not sure if anyone else has had similar results. Other than it being warmer I can't seem to think of anything else that could of done it. I ran 37 inch Goodyear Kevlar MTRs all summer last year and never got better than 17.3 Mpgs average with my local driving. I have been running the current 37's Kanati Trail Hogs since October of last year and it stays in the 70's and 80's around here until around December. I was only getting around 17.3 Mpgs with them as well with my local driving. I may be able to get it even higher over the next few days. It's interesting to me. I wouldn't think the wheels sticking out some would make a difference. Any thoughts on it? Video for reference

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[Mr.Wilson]

Stupid question here among many that I have. (New gladiator owner here ). How do you set the cluster to see what gear you are in while driving?

Also What other mods have you done as far as helping MPG’s?

 

[sharpsicle]

Looks like you're still only averaging 17.5. That's not a real impactful improvement, especially if you're going by the lie-o-meter on the dash. Have you calculated MPGs based on fill-ups?

 

[Jeeperjamie]

Stupid question here among many that I have. (New gladiator owner here ). How do you set the cluster to see what gear you are in while driving?

Also What other mods have you done as far as helping MPG’s?

It's in the settings on the menu. While in park you just scroll through and you customize what you want to see.

As far as anything else to improve Mpgs the answer is no. I did put thought into my setup after building a few jeeps over the years and dealing with crappy MPGs in decided to think about ways I could salvage some Mpgs on this build. I took weight into consideration when choosing my bumpers and winch also I went with a full width bumper instead of stubby bumper to help force the wind around the jeep instead of wind getting up inside of the fenders and causing lag. My tires, 37 12.5 17 Kanati Trail Hogs only weight 72lbs so they are on the lighter side of choice's. I also let the auto Start/Stop do it's thing and I don't turn it off. Other than that I think the weight factor and bumper choice and a non M/T tire are key factors in the Mpgs. Plus mines a Max Tow as well and it's got the 4.10 gears. It sits currently for reference

 

[Jeeperjamie]

Looks like you're still only averaging 17.5. That's not a real impactful improvement, especially if you're going by the lie-o-meter on the dash. Have you calculated MPGs based on fill-ups?

Yes I have calculated based on fill-up s and it's slightly better by calculating it by hand around 17.8 but it's pretty close to what I'm seeing on the dash. It's up to 17.6 as of this morning on my commute to work which is exactly the same hour round trip I take 5 days a week so nothing has changed as far as route or anything. I'm pretty impressed to be getting that good of Mpgs on 37's honestly. I was considering a regear but haven't really felt the need to yet. I'm still seeing 7th and 8th gear pretty regularly.

 

[JTR178]

I would kill for 17 MPG.

[Cries in 14 MPG]

 

[ShadowsPapa]

Yes I have calculated based on fill-up s and it's slightly better by calculating it by hand around 17.8 but it's pretty close to what I'm seeing on the dash. It's up to 17.6 as of this morning on my commute to work which is exactly the same hour round trip I take 5 days a week so nothing has changed as far as route or anything. I'm pretty impressed to be getting that good of Mpgs on 37's honestly. I was considering a regear but haven't really felt the need to yet. I'm still seeing 7th and 8th gear pretty regularly.

If you have used the odometer to set the tire size and it's dialed in really close, the cluster mpg display will be extremely close. The deviation people get from "hand calculations" (I use FillUp app) is because you can't possibly fill the tank to the exact same level every time, the temperature of the fuel matters (gas expands when warm) and other factors. So people believe the cluster is wrong when really it is they who aren't all that accurate. The cluster is really close in every case on mine - Mine is extremely close - over TIME.
Some fills are spot on, some are showing the cluster high, others showing the cluster mpg as low, but over time, they average really close, within tenths.

Anyway - you have removed spacers which means the tire fronts aren't out in the wind as much.
Ever notice how vehicles geared for mpg have the fronts of the tires hidden from the oncoming air? Even semi tractors often shield the fronts of the tires and fill the deep rim recesses. Some of the JT sports have that bumper-to-fender filler - keeping the oncoming air from hitting the fronts of the tires.
My bet - your tires were catching air, and the more aggressive the tire tread, the worse it makes it. Stick those tires out there and expect lower mpg.

Of course as the ambient air temp rises, the air is less dense, also presenting less drag and less "wind resistance" so when the air temp goes up 10-20 degrees, expect slight increases in mpg.

With slightly warmer temps, my mpg has risen by 1 mpg.

 

[Jeeperjamie]

If you have used the odometer to set the tire size and it's dialed in really close, the cluster mpg display will be extremely close. The deviation people get from "hand calculations" (I use FillUp app) is because you can't possibly fill the tank to the exact same level every time, the temperature of the fuel matters (gas expands when warm) and other factors. So people believe the cluster is wrong when really it is they who aren't all that accurate. The cluster is really close in every case on mine - Mine is extremely close - over TIME.
Some fills are spot on, some are showing the cluster high, others showing the cluster mpg as low, but over time, they average really close, within tenths.

Anyway - you have removed spacers which means the tire fronts aren't out in the wind as much.
Ever notice how vehicles geared for mpg have the fronts of the tires hidden from the oncoming air? Even semi tractors often shield the fronts of the tires and fill the deep rim recesses. Some of the JT sports have that bumper-to-fender filler - keeping the oncoming air from hitting the fronts of the tires.
My bet - your tires were catching air, and the more aggressive the tire tread, the worse it makes it. Stick those tires out there and expect lower mpg.

Of course as the ambient air temp rises, the air is less dense, also presenting less drag and less "wind resistance" so when the air temp goes up 10-20 degrees, expect slight increases in mpg.

With slightly warmer temps, my mpg has risen by 1 mpg.

That's why I trust the cluster, it seems to be pretty accurate at telling how many miles to empty I have and the fact that each fill-up might be more or less gas each time. My speedo is pretty much dialed in. I've used police radar on my buddies police cruiser, The little things they set out to show your speed, and 2 or 3 gps apps while not connected to the Jeep, all seem to be within a few 10ths of being dead on.

I knew it would go up again when it started warming up but my big take away from it is how much easier it's been the past few weeks to keep the MPGs at or above the normal 17. I have been doing it for over a year but these past few week, especially the past 6 days, it's been steadily climbing more than it ever has. I truly believe the tires sticking out made a difference in the aerodynamics. When or if I consider new wheels I'm going to take that into consideration for sure

 

[Labswine]

Stupid question here among many that I have. (New gladiator owner here ). How do you set the cluster to see what gear you are in while driving?

When you move the shift lever to the left, putting it in manual mode, it will automatically display the gear you're in on the dash. You don't need to do a thing.

 

[Jeeperjamie]

When you move the shift lever to the left, putting it in manual mode, it will automatically display the gear you're in on the dash. You don't need to do a thing.

I think he was asking how to do it without it being in manual mode and you have to set that inside the settings where you customize the display. There a few different ways you can setup to display different things.

 

[ShadowsPapa]

When you move the shift lever to the left, putting it in manual mode, it will automatically display the gear you're in on the dash. You don't need to do a thing.

Don't need to go into manual mode. I set mine up right after I bought it so can't recall the exact steps but it's doable when you are sitting still in setup mode in the cluster.

 

[Edub]

I would kill for 17 MPG.

[Cries in 14 MPG]

you and me both buddy. this guy drives a unicorn and shouldn't change anything else.

 

[ShadowsPapa]

I'm doing 19+ again and that's with A/T tires (those dropped the MPG some) and the extra weight of a steel bumper, winch and skid plate (which dropped mpg another 1 or so)
I used to run low 20s with ease.

 

[Jeeperjamie]

Well after the ride home today

I'm considering trying to fab something up to close in this area that doesn't look terrible and see if it goes up some more.

This is the best I've gotten around town on 37's

 

[MCATDT]

OMG more gas mileage dribble. You bought a Jeep..its a box on wheels and you modified it with bigger wheel, tires and spacers to get it to look like you wanted. Stop already.....if you want MPG go buy a Prius and park the Jeep until the pain at the pump is one you can tolerate. My Jeep happily runs on recycled dinosaurs and looks damn good doing it!!!

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