GreenMachine10

Hey everyone. I'd like to start this review off by telling y'all about my rig. I have an AEV 3.5 in lift with 35 in BFG KM2 tires. I have RR front and rear bumpers and a tire carrier for my full size spare. I drove this set up as my DD for about six months. I love the looks and performance of my set up, but I was unimpressed with the JEEP's performance(power and MPG). With this setup my rig was sluggish and the MPG were terrible (11.8 AVG). So, after ALOT of research I decided I needed to re-gear the axels. I had 5.13:1 gears put in along with a master install kit. When I got it back here is what I found. The power is MUCH better, like stock I would say. But, the MPG's stayed exactly the same, WHY?? I thought it was supposed to improve it. I pro-cal'd the ECU. My over-all rating for this job is a 7/10, power is great and is a must for my setup, but what really drags is that the MPG did not improve. Lots of people were saying they get between 15-16 with the same type set-up. So, do not re-gear for MPG. Only for power. Which is great BTW.

joe002

I have 5.38s but get the same MPG with 5.38s and 35s as I did with 4.10s and 32s - 15 MPG.

TimberwolfFXDL

Did you guys recalibrate your speedometers for the increase in tire size before calculating fuel economy? If not, your numbers are likely way off. Remember that whether you calculate it yourself or let the ECM do it, if neither of you knows the TRUE number of miles driven (because your speedo is off, which therefore means your odo is off too), and so it will appear your mileage has gone down much more than it really has.

Going to 37s with stock gearing dropped my mileage shown in the little screen to around 14, where I was always 16 or so in the past. But when you consider I'm driving more miles than it thinks I am, and still using fuel close to what I normally would, of course the calculation is going to be off.

I'd wager this is what a LOT of people are really seeing when they complain of MPG drop. Of course there will be some drop, especially in city driving, but I'd bet it's not as bad as you think

GreenMachine10

Yes, I have the pro-cal from AEV, so I have done all the proper calibrations.

JPop

Robot Lords of Tokyo are smiling and eating kittens.

GreenMachine10

Oh shit!! It's changed haha. JEEP!!!

ntropy

I have the AEV 3.5", 35" BFG MTs, and I also re-geared to 5.13's about 8 months ago. With this setup, and withOUT a heavy foot in town, I average about 15mpg in town. If I run a whole tank on the freeway, again, staying generally at the speed limit, I can still get 17mpg.

I have a Schrockworks rear bumper/tire carrier and Schrockworks rockrails. Those are some heavy sunofaguns.

I think even with re-gearing, your MPG depends MOST on how you accelerate, not as much on bumpers, rockrails, etc. Trying for the good 0-60 time and buzzing along at 75mph+ will both push you down several MPG's.

GreenMachine10

Thats pretty good milage!! I have never hand calculated it yet. Plus, my rig only has 6200 miles on it. Will it improve as time goes on??

joe002

Yes, and verified with a GPS.

GreenMachine10

I have tuned it with the procal, Is the superchip better?