Mileage after gear job!?!

T

TJ905

New member
So recently I had 4.56s, a truss and my 35" MTZ installed. I trussed the D30 (don't judge me) just for peace of mind. I also run 3" spacers and a few other goodies to keep the suspension in check.
I had the gears done because my 2014 Sahara with the 3.21 gears was attrocious with the 35s. It was liveable with just me in the vehicle, it is a 6spd. But with my buddies or any cargo it was unbearable.

After doing some research, I wasnt expecting excellent mileage from my lifted Jeep on 35s. However I was'nt expecting it to be as horrible as it is. Mind you it has been -35C often with these last few tanks of fuel. 87octane is what I use. I am getting around 17l/100km. It has been calibrated with an AEV Procal for the tires and the gears.

Any advice, suggestions or help would be awesome!
 
wayoflife

wayoflife

Administrator
Staff member
Being that you control your shifting, calibrating your speedo won't make a difference on a 6-speed other than to give you a more accurate reading to do your math with. Assuming you did measure from the center of your wheel to the ground and x2 instead of using AEV's instructions which are WRONG, you should have an accurate reading. Having said that, taller gears will technically give you better fuel economy on long flat drives as they'll allow you to run at a lower RPM at higher speeds. Where a higher gear ratio helps is in stop and go conditions or in areas where you do a lot of climbing as they will allow you to get up to speed faster and hold it on a hill without having to rev up too much.
 
13_gecko_rubi

13_gecko_rubi

Caught the Bug
We had a post going on our club board just a couple days ago on this. Most of my Canadian friends are getting 18-20l/100 km right now on 35s so you are in line/better than them.

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jeeeep

jeeeep

Hooked
TJ905 said:
So recently I had 4.56s, a truss and my 35" MTZ installed. I trussed the D30 (don't judge me) just for peace of mind. I also run 3" spacers and a few other goodies to keep the suspension in check.
I had the gears done because my 2014 Sahara with the 3.21 gears was attrocious with the 35s. It was liveable with just me in the vehicle, it is a 6spd. But with my buddies or any cargo it was unbearable.

After doing some research, I wasnt expecting excellent mileage from my lifted Jeep on 35s. However I was'nt expecting it to be as horrible as it is. Mind you it has been -35C often with these last few tanks of fuel. 87octane is what I use. I am getting around 17l/100km. It has been calibrated with an AEV Procal for the tires and the gears.

Any advice, suggestions or help would be awesome!
Click to expand...


you're getting about 14mpg, not bad considering you only geared to 4.56 and are running a truss and 35" mud tires + 3" lift


I have a 3.8 auto with 4.88 gears, 3.5" lift, PR44 up front and 35's. when I drove it the 1st time with the PR44 I could feel the difference, it's heavy! but still manage an average of 14-15 mpg, if I drive more carefully then I can squeeze a bit more. on the freeway at 60mph I can get 18+ mpg.......until I hit a head wind or incline lol

I did remove my skids and gained some mileage but now I have to put them on every time I plan a trip. we'll see if it's worth the mileage difference (if it makes any difference) for the time it take to remove/install them.

What kind of mileage were you getting before that 17l/100km makes it unbearable?
 
T

TJ905

New member
I suppose unbearable isnt the word. I didnt buy the Jeep for economy. I bought it to be awesome. I was just wondering what others with similar mods were getting. I have the hardtop on and use cruise when I can. My understanding is that the "ECO" light isnt as important as the load on the engine.
 
T

TJ905

New member
wayoflife said:
Being that you control your shifting, calibrating your speedo won't make a difference on a 6-speed other than to give you a more accurate reading to do your math with. Assuming you did measure from the center of your wheel to the ground and x2 instead of using AEV's instructions which are WRONG, you should have an accurate reading. Having said that, taller gears will technically give you better fuel economy on long flat drives as they'll allow you to run at a lower RPM at higher speeds. Where a higher gear ratio helps is in stop and go conditions or in areas where you do a lot of climbing as they will allow you to get up to speed faster and hold it on a hill without having to rev up too much.
Click to expand...

I did follow the instructions :( Will the calibration effect the MPG reading i get on the dash??
 
MedixJK

MedixJK

-
TJ905 said:
I did follow the instructions :( Will the calibration effect the MPG reading i get on the dash??
Click to expand...

If your refering to the computer calculated mpg, then absolutely, as your "tire size" measurement will be off. The right way, as Eddie said, is to measure from wheel center to flat pavement (radius), the multiply that number by 2 (diameter). This takes into account the squished side of the tire against the road.
 
Twiztid11

Twiztid11

New member
I have a 2014 6 speed. Stock I was getting about 24mpg. It was LOVELY! lol......After a 3.5" lift, 35's, and 4.88's I get about 17-18mpg and it is well worth it because I get more SPG (smiles per gallon). :blush:
 
hbkid22

hbkid22

Member
So I may be one of the lucky few. I put 513s in my sport 2dr 6spd (D30 still) and have 35s and shot back up to 16/17mpg.....
 
ERAUGrad04

ERAUGrad04

Caught the Bug
While running 35" BFG KM2s and 4.10 gears, I was seeing around 13.5 in the city and 15.5-16 on the freeway. I really wouldn't expect much more than 15-16 with 35s.
 
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