fishinjk

I wasn't as bad off as Hulk but I was only getting like 15 city 16 highway, and that was on the 29s that came factory. Now with 35s im getting around 14.5 everywhere. All hand calculated.

T Mac

I got as high as 23 on a highway trip with a 6 mile trail at the end. That was driving about 65 mph and bone stock. Since then, I've added the Warn bumper, a Mile Marker winch and 32" BFG MTs. I haven't driven the same road since, but on the interstate at 75 MPH, I get about 19-20. Of course, this is driving up and down the Colorado Rockies, so no complaints.

Lemay427

i am getting 17.5 with the smallest tires from the factory and 4.10s. I am looking to put on a 3" with 35's next month so I hope i can maintain some of the mileage

saltman

15-16 mixed 16.5-17 highway here. stock rubicon 2dr 2500 miles

HULKGREEN

Hey guys , It's me the guy with really crappy fuel economy.

Well I decided to try for broke and put my stock tires and aluminum rims back on my Awesome looking Jeep. I took off the Mickey Thompson MTZ 33s on Crager soft 8 steel rims..... ..........It looks so mundane with a 2" lift and stock tires and rims......but to the point


According to the dash display IT Immediately increased economy by 2.5 to 16.5 city/hiway combined and that is only in the first 40-50 miles....Yes I know my dash display is the biggest liar I know, but even a realistic 14.5 is better when previously on a long trip 14.3 was the best I could get at 70mph.

??? Does anyone think the weight difference was the issue????

john98026

Well, it looks like the results are in, although a bit mixed. I will be swapping my 3.21s for 4.10s and maybe, just maybe, I can pull the passes at or near the speed limit

TKDTPOF

Weight Issue?? NOPE I don't think so! -- Unless you had the Computer flashed for the 33's.

Did you calculate in the fact that the Odometer was Off (low) by @ 13% when you had the bigger tire/wheel combo?

IE: 33"/29" = @ 1.13 so for every 100 miles on the odometer you actually went approx 113 miles. So if you multiply the 14.3 x 1.13 you get -- 16.15 MPG with the bigger tire/wheel combo.

If you are getting 16.5 now (vs 16.15 calc above)...that's probably due to the lessened Rolling Resistance from the smaller wheel/tire combo.

HULKGREEN

I can agree with the rolling resistance idea 100%. Because Mickey T's are soooo much wider. But, on the math my stock tire is 255/75/17 measure 32.3 inches tall not 29. Mickey T's 33x12.5x17 measure 32.8 which happens to be the same diameter as a stock rubicon tire.


In fact, I put my GPS unit up to this test and my speedometer with the 32.8 was dead nuts on the mark perfect... My stock tire is off by a fraction!!!!!!!



And thank you, I appreciate any info/ new ideas to my dilemma!!!!!