Simple question, what is your mpg's for 4.88 gears and 35s? I get prolly around 8 mpg with my 3.55s and 35s and I'm re gearing to 4.88s soon and I want to know approximately what I'll be getting. After all my xj is my DD.

 

you'll probably be in the 13-15mpg range depending on how heavy you wheels are, how much armor you have, with or without a roof rack, and how your XJ runs

 

No armor or roof rack, it's still the beginning of my build, tires are 35s soooo yea there pretty heavy lol but 14 mpg sounds amazing compared to like 7 or 8 and I'm planning on doing some engine and exhaust TLC to get her running more efficient.

 

im running 4.56s instead of 4.88s with my 35s, my xj has t-case skid, longarm kit, gas tank skid, rock rails, quarter armor, front and rear bumpers, and a roof rack. keeping my speed on the highway around 65 i get 16mpg. still has plenty of power with 4.56s does good offroad too. with 4.88s the fuel economy would be less because of it spinning a little bit higher rpm. at 65 with 4.56s the engine is spinning 2250 rpms which is stock i believe. 4.88s will put it at 2500 rpms

 

Jeez, I can't get more than 12 with 30x9.5's.

 

poor driving habit.......

 

15 mpg highway with 5.38s and 35s here. Fully loaded with camping gear, 3 guys, spare parts and tools.

 

Your mpg is inaccurate if have bigger than factory tires and did not change the speedo gear. Especially if you changed the gears

 

I'm running 4.88 gears, 35 inch tires, and winch, bumpers, sliders, and a couple of hundred pounds of tools and spares. I get a little over 15 mpg driving between 55-65 mph on local highways, and between 12-14 driving 30-40mph on grave roads.

Of course the speedometer gear has been changed.

 

I got 13 with 33s and 4.88s in the mountains. Haven't calculated it on normal flat ground.

 

Add like 20% to your mileage and then calculate your mpgs, assuming you havent changed speedo gears

 

Why would you do that? Wouldn't it be better to calculate how far off the speedometer is then calculate the difference in mileage.
TireRack gives the revolutions per mile for different sizes of tires so it is easy to calculate how far off the speedometer is for your tire size.

 

I know. I didn't actually calculate it but I'm just estimating that its around 7 or 8 now.

 

I went by GPS.

 

I baby this thing. It's a jeep, I'm not complaining. Just saying.