What MPG are you getting?
- Thread starter jsmusic
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Red and Black LJs — stock autos with 31"s get 13-14mpg. The White Rubicon LJ 6-speed was getting 8-9mpg on 31"s, but the thermostat was failing (open and running very cool) and I had a vacuum leak, both issues are all fixed, so I hope to get better than the autos now.
Like you, I have driven a manual all my life. No, wait.. I had two auto's mixed in there but the boredom-induced trauma self-deletes from my memory.
Anyway, I've always wondered what be better for MPG (and for parts wear).. Downshifting and using compression braking to slow, or coasting in neutral and using the brakes.
Back on topic.. I just re-geared to 4.56's. Had nothing to do with mpg and if I saw any change either way it was a necessary evil given my desire to regain fifth, counter the effect of 33's and get back into the power band. Short story is with the three tanks I have consumed since the re-gear, with the same driving style as prior, I am seeing about half a mile per gallon improvement. Make of that what you will.
How long do you expect it to take to recoup the cost of the gear install?
If you count happiness as a dollar figure not long at all. One tank of gas maybe
James9100
TJ Enthusiast
I’ve been wondering the same thing, I’m new to stick and just been trying to learn the most optimal way to drive in terms of fuel economy and wear and tear.
Not sure about mpg's but for wear I can say in all the years I have driven a stick, I've done only one clutch (which was an upgrade not a worn replacement) and brakes less than a half dozen times (when they were actually needed). Something to be said for compression braking as long as you are rev-matching
I'd rather change breaks 10 times than a clutch once. Compression breaking is for long steep hills and heavy loads.
As for mpg it's a trivial difference. If you have an obd gauge you can watch instantaneous mpg. Above certain speeds and rpms it cuts fuel completely so it's better coasting in gear, but once the fuel is back on you'll burn more at the higher revs. For a general guideline I'd guess that coasting in neutral will result in better milage most of the time.
Yep. I've always used compression braking, even with automatics. Just the way my daddy taught me. I've never worn out a transmission, have ever only replaced one clutch - which has a "story" - and people look at me like I have 3 heads when I tell them that brakes should go about 100K miles - maybe more!
Seeing as this thread still lives...
Attempt at getting some data on going from regular dino to full synthetic. Picture for the product I used. Not looking to get into the weeds of which oil is better but I guess you can see my favorite choice. I took the best 2 MPG values of 4 tanks driving from Everette, Wa to Boise, Id Average 16.80 MPG-- almost all of highway(65-75 mph in WA). I took the 2 worst of 3 tanks post oil change- average 17.65- mostly highway (65-80mph in idaho). I would go best 2 out of 4 but it sounds like winter blend gas has hit the local market and honestly I would like to move on to doing my tune up this weekend. The reason for comparing the two best and two worst is just to compensate for potential variables. If use all three its opens the spread to 16.43 vs 18.02 So thats the numbers. I will keep tracking but this will be the cleanest of an A/B test that I can do.
Disclaimer:
- I used actual odometer readings through out, just measure delta of potential improvement- pretty sure odometer is 3% off taking these numbers down 3% if your looking for comparison to your Jeep.
- rear differential I used 75-90 which is likely a lighter oil than what was in there. All other weights were at recomended.
- Standard transmission on this- So all 5 drivetrain components were change. I dont think automatics are going to realize the same delta. Certainly would chase a full synthetic automatic change over unless you it gives you peace of mind and you have the $$.
True story.. my wife can't drive a manual. Truth is she isn't a good driver by any stretch. And she is even worse at being a passenger. She yelled at me because she felt I was too aggressive and "hates when every one is braking and and accelerating " when I should be braking. She though rev matching was accelerating.
Am i only one who cringes at a fact that some of you have worse efficiency than a uhaul box on wheels, not even mention some of the semi trucks ...
It is what it is,I have my original window sticker,and with my 23rh I think it says 13 mpg and there is a stipulation on that at the very bottom
Don’t know about you EB, but to me my rig is a whole lot more fun than a uhaul box on wheels…
4.0, NG3550, 33x11" Maxxis Razors
I was getting about 10mpg on a good day throughout the summer. Then The engine light finally came on and motivated me to replace the upstream o2 sensors.
I was 1/4 into a tank before the sensor replacement, but I'm on track for closer to 15mpg so far. Next tank will be more accurate.
Of course P0432 came back today...so downstream o2 are getting replaced as soon as I get the parts. If I gotta replace the Y pipe I will, but the o2 sensors are who-knows-how-old anyways...
I was getting about 10mpg on a good day throughout the summer. Then The engine light finally came on and motivated me to replace the upstream o2 sensors.
I was 1/4 into a tank before the sensor replacement, but I'm on track for closer to 15mpg so far. Next tank will be more accurate.
Of course P0432 came back today...so downstream o2 are getting replaced as soon as I get the parts. If I gotta replace the Y pipe I will, but the o2 sensors are who-knows-how-old anyways...
I just replaced all 4 of mine,it might have helped 1 mpg Ish,went from 9mpg to 10.5 on our last trip to Colorado,but right now I’m carrying a whole house with me
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Pantera99
TJ Enthusiast
I had a code for one of the upstreams so I replaced both. Downstreams haven't had a problem but I was thinking of doing them just for the heck of it.
Head Lice
TJ Addict