CEThomas Posted February 24, 2008 Share Posted February 24, 2008 Looking for someone with a set up close to ours so we can see about what MPG we are looking at. 4.0 HO AW4 6.5" lift 3.55 Axles 33" tires I am think about 16mpg for our set up?? Link to comment Share on other sites More sharing options...
89eliminator Posted February 24, 2008 Share Posted February 24, 2008 4.0 AW4 6.5in lift 33s 4.10s about 15-17 city, 20 highway. Link to comment Share on other sites More sharing options...
Eagle Posted February 25, 2008 Share Posted February 25, 2008 Looking for someone with a set up close to ours so we can see about what MPG we are looking at. 4.0 HO AW4 6.5" lift 3.55 Axles 33" tires I am think about 16mpg for our set up?? What RPMs do you turn at 65 MPH, about 1200? I think if you get better than about 12 MPG it's a modern miracle. Link to comment Share on other sites More sharing options...
offroader461 Posted February 25, 2008 Share Posted February 25, 2008 87 MJ: 4.0 5spd 6" lift 4.10's 33"............20-22MPG 90 XJ: 4.0 AW4 4" lift 3.55's 32"............18-19MPG Link to comment Share on other sites More sharing options...
CEThomas Posted February 25, 2008 Author Share Posted February 25, 2008 Looking for someone with a set up close to ours so we can see about what MPG we are looking at. 4.0 HO AW4 6.5" lift 3.55 Axles 33" tires I am think about 16mpg for our set up?? What RPMs do you turn at 65 MPH, about 1200? I think if you get better than about 12 MPG it's a modern miracle. Not sure, never had it up to 65 yet. But we are getting around 8mpg :roll: Going to put in a new O2 sensor and see what we get. Everything else is new so it must be a bad O2 sensor. Link to comment Share on other sites More sharing options...
CEThomas Posted February 25, 2008 Author Share Posted February 25, 2008 With what everyone else is getting, 11-13 mpg should be my goal :roll: Link to comment Share on other sites More sharing options...
warf90 Posted February 25, 2008 Share Posted February 25, 2008 I have 4.10 gears with 33" X 12.50 and I am getting 15 mpg. Link to comment Share on other sites More sharing options...
Randy in Maine Posted February 25, 2008 Share Posted February 25, 2008 My 1990 MJ stock 4.0 5 speed 3.07 axles Michelin M/S 205/75/15s gets 22-23 mpg Runs 2250 RPMs at 70 mph 33 x 10.5 x 15s are 18.08% taller than stock and will throw off the odometer unless you have corrected for it. Link to comment Share on other sites More sharing options...
JeepcoMJ Posted February 26, 2008 Share Posted February 26, 2008 3.55 31x10.50 22-23mpg. ohhhhh that's right. i'm rockin a 3800 camaro motor with a 5 speed... :P can't wait for 33's and 4.10 gears. gas mileage will go through the roof. edit: I did get 24.5 mpg on a tank once...but it was completely interstate driving except for the on ramp and exit ramp. :D gas to badlands won't kill me that's for sure Link to comment Share on other sites More sharing options...
CEThomas Posted February 26, 2008 Author Share Posted February 26, 2008 Have not changed the speedo gear yet, but the speedo is off by 6mph. Checked by GPS Link to comment Share on other sites More sharing options...
JeepcoMJ Posted February 26, 2008 Share Posted February 26, 2008 Have not changed the speedo gear yet, but the speedo is off by 6mph. Checked by GPS if you haven't switched the speedo gear, you have no idea what kind of mileage you're getting. it's probably better than you thought. Link to comment Share on other sites More sharing options...
Randy in Maine Posted February 26, 2008 Share Posted February 26, 2008 I went back to stock tires (205/75/15) as the ones on there before (235/75/15) geared me up too much with my 3.07 axles. I just ran out of torque too often. If you go here http://www.1010tires.com/TireSizeCalculator.asp you can compare various sizes at the same time. Link to comment Share on other sites More sharing options...
summerinmaine Posted February 26, 2008 Share Posted February 26, 2008 I went back to stock tires (205/75/15) as the ones on there before (235/75/15) geared me up too much with my 3.07 axles. I just ran out of torque too often. If you go here http://www.1010tires.com/TireSizeCalculator.asp you can compare various sizes at the same time. Interesting. Mine with 3.07s has 235/75s and I've noticed that it runs out as well. I've also thought I was only getting about 14-16mpg, but maybe I need to be a bit more careful in my calculations. Link to comment Share on other sites More sharing options...
CEThomas Posted February 26, 2008 Author Share Posted February 26, 2008 Have not changed the speedo gear yet, but the speedo is off by 6mph. Checked by GPS if you haven't switched the speedo gear, you have no idea what kind of mileage you're getting. it's probably better than you thought. Maybe not, But you have 1/4+ tank of gas and you stop and put in $10 ( 3 gal) in it and you drive to Lancaster and back which is 45 miles round trip and you run out of gas, well it's not getting good mpg :nuts: And during the trip you can see the gas guage go down from 3/4 to E, I may be off 1 mpg but not much more. The 4.0 did run good :cheers: Link to comment Share on other sites More sharing options...
dragonrider477 Posted February 26, 2008 Share Posted February 26, 2008 1988 mj 4x2 long box,4.0,5 speed,3.55 with correct speedo gear and gps verified,205 75 15 tires,bedliner and cap,750 mile road trip from ny to tn ave speed 70 mph,23.5 mpg for trip. Link to comment Share on other sites More sharing options...
billyray Posted September 21, 2008 Share Posted September 21, 2008 horrific gas mileage, 10-12 miles per gallon. Everything stock, auto, 4.0, runs greats. Guy at the store told to change the "MAPPS", if you're sitting in the driver's seat and made a straight line to under the hood it's a sensor looking thing straight from the steering wheel. Link to comment Share on other sites More sharing options...
mvusse Posted September 21, 2008 Share Posted September 21, 2008 87 4.0/AW4 3.55, 235/75R15 I get about 18 around town, 22 on the highway, 24 if I don't go over 65mph. Those numbers are corrected for tire size and double checked with GPS. I got 13-14 around town at first, 18 on the highway. Then I found a broken plug wire cause me to run on only 5 cylinders. Link to comment Share on other sites More sharing options...
JeepcoMJ Posted September 21, 2008 Share Posted September 21, 2008 well, 6mph off means you're something like 12% off roughly. so, take every FULL TANK and refill it to full. then multiply the miles travelled on the previous tank, and multiply times 1.12 ...then divided that number by the amount of gallons you used to fill the tank. so, 186 miles x 1.12= 208.32miles 11.07 gallons = 18.81842818428184281842... should figure out which speedo gear you need and replace it. the 3800 was off by 13% and i was getting 19mpg before doing the math. anyways, my 87 is 4.0 auto 4wd 4.10 gears 33x10.50's and it averages 17mpg, though i have gotten 18mpg in town and 21 on the highway. it also runs like crap and needs new o2 sensors, coolant flush, and needs a rear main pretty bad. Link to comment Share on other sites More sharing options...
JeepcoMJ Posted September 21, 2008 Share Posted September 21, 2008 well, 6mph off means you're something like 12% off roughly. so, take every FULL TANK and refill it to full. then multiply the miles travelled on the previous tank, and multiply times 1.12 ...then divided that number by the amount of gallons you used to fill the tank. so, 186 miles x 1.12= 208.32miles 11.07 gallons = 18.81842818428184281842... should figure out which speedo gear you need and replace it. the 3800 was off by 13% and i was getting 19mpg before doing the math. anyways, my 87 is 4.0 auto 4wd 4.10 gears 33x10.50's and it averages 17mpg, though i have gotten 18mpg in town and 21 on the highway. it also runs like crap and needs new o2 sensors, coolant flush, and needs a rear main pretty bad. Link to comment Share on other sites More sharing options...
HOrnbrod Posted September 21, 2008 Share Posted September 21, 2008 Yeah, MPG is definitely important, and getting more importanter every day. :D Current setup: 4.5L stroker w. AW-4 4.11 gearing 31" BFG MTs Correct speedo gear 15 around town, 18-20 highway. According to similar setups on the strokers forum, this is not too bad, a bit above average. Got all the parts, and next week I am swapping my old intake for the 1999+ curved runner unit, and adding a Unichip, then having it dyno tuned at Hesco. This has resulted in 2-3 more MPG for most w. 10% overall HP/torque numbers. We'll see............. Link to comment Share on other sites More sharing options...
FxRacing282 Posted September 21, 2008 Share Posted September 21, 2008 Looking for someone with a set up close to ours so we can see about what MPG we are looking at. 4.0 HO AW4 6.5" lift 3.55 Axles 33" tires I am think about 16mpg for our set up?? What RPMs do you turn at 65 MPH, about 1200? I think if you get better than about 12 MPG it's a modern miracle. Not sure, never had it up to 65 yet. But we are getting around 8mpg :roll: Going to put in a new O2 sensor and see what we get. Everything else is new so it must be a bad O2 sensor. you can try it but its no guarantee. synthetic oil and a good tune up should give you much better mpg. Link to comment Share on other sites More sharing options...
92comanche4x4 Posted September 21, 2008 Share Posted September 21, 2008 I'm getting 12 all country roads and i got a 3in lift 3.55's 4.0 auto and 31/10.5/15 Link to comment Share on other sites More sharing options...
Redramman Posted September 21, 2008 Share Posted September 21, 2008 Release parking brake! :D I don't know what mpg the Comanche gets,My Son drives it and he spends $50 and that only gets 3/4 tank.To figure mpg always start with full tank drive till it's at least down to 1/2 tank write down miles fill and write down gallons etc.... The gas gauge is just not accurate enough to tell how many gallons you use. Anyway I get 12.5 mpg in my 6300lbs 1999 RAM 2500 4x4 360 V-8 (gas) auto trans 4:10,with 35"tires (and yes the spedometer has been corrected),so something is not right with your truck. Link to comment Share on other sites More sharing options...
FxRacing282 Posted September 21, 2008 Share Posted September 21, 2008 yeah my 5200lb chevy with a 350 with 35x16 boggers and 3.42 gets about 10city -15highway that is low. have you checked fuel injectors? Link to comment Share on other sites More sharing options...
BREEZE1 Posted September 22, 2008 Share Posted September 22, 2008 I'm getting about 1 gallon pre month. It has a lot to do with it sitting on jack stands! One of these days I hope to get worse gas mileage. :roll: Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now