Northern Virginia Jeepers Association

Open Discussion (Club Members and Non-Members) => Jeep Discussions => Topic started by: RFH_98TJ on June 12, 2018, 01:38:06 PM



Title: Another gas mileage thread
Post by: RFH_98TJ on June 12, 2018, 01:38:06 PM
I usually "drive it like you stole it" with my TJ and am lucky to ever see anything over 11.5mpg.  It's a Sport with 4.0, AC, 4" lift, 33s, manual, 4.56, and some armor to weigh it down.  I drive 10 miles to work each way from Lorton to the Prince William County stadium area on the PW Parkway.  I use mostly I-95 and the PW Parkway hitting well over 70 on I-95.  Then it's just a few lights and of course I may go out to lunch or run a few errands.  Barely ever even getting near 12 mpg on a good week.

Going to the NTJR I followed along in the conga line with everyone else following behind Bill pulling his rig.  We were pretty much 60 to 65 most of the way but no cruise control - just putting along.  I filled up at Haymarket before we left.  Drove 94.6 miles to the Sheetz in Harrisonburg, and could only put in 4.66 gallons of gas.  I tried to get more in, but that was full to the top.  It kind of surprised me and I was in disbelief.  I finally remembered to do the math today.

94.6 miles divided by 4.66 gallons equals 20.3mpg.  How is this even possible?  I've always read on Wrangler forum people getting between 17 to 20 in stock form and a limited few that mention they get over 20.  It seems the 4-banger doesn't do too much better in the gas mileage range, it just has less power (from the reading I have done).  Of course us Jeepers with the lifts and big tires just laugh and say we get 10 to 14 on a good day, and think that is the norm.  But I guess it doesn't have to be.

I guess I will try to slow myself down a little bit on longer trips.  I also have an OEM electric fan from a 4-banger that I have been contemplating putting on to help improve gas mileage.  Now I'm still undecided whether to do it or not from this recent development.


Title: Re: Another gas mileage thread
Post by: zuke on June 12, 2018, 02:00:22 PM
It's amazing how much of a difference slowing down can make in these less than aerodynamic boxes.. I regularly got 16mpg out of my 4 banger/33s when it was on the road, but slowing down to 60 would bring it up into the low twenties...

Never cared enough about mileage to keep it down to 60 for long :D


Title: Re: Another gas mileage thread
Post by: RattleTrap55 on June 12, 2018, 02:24:14 PM
I am a CJ with a 4.2L converted to multi-port fuel injection, 4.10 gears, riding on 12.5" wide 33" tires, 5-speed, and not much else. I track my mileage with every fill up (I have no fuel gauge) my average is between 15.5 & 17 mpg. Most of my driving is in town or short highway trips. I rarely drive much faster than 65 mph in the CJ. Like you I filled up before leaving for the NTJR. I drove 149 miles before topping off at the Sheetz in Harrisonburg and I mean really topped off, fuel bubbling out topped off. I could only get 7.2 gallons in the tank establishing a new record for the CJ of 21 mpg :eek.  I have not  purchased fuel since the NTJR run so I do not know what my return mpg will be.



P.S. I am not sure how you were able to pass me twice on the way home unless you where on your second trip around the planet when I saw you on 66 :?.



Title: Re: Another gas mileage thread
Post by: RFH_98TJ on June 12, 2018, 02:30:28 PM
I bent the space time continuum to do that.  Travelling at light speed is pretty cool in that way.  :8


No wait.  I think I may have stopped for gas, some dinner, and maybe watched a movie in Mt. Jackson then took off again.


Title: Re: Another gas mileage thread
Post by: z4iken on June 12, 2018, 03:06:41 PM
I commute 10 miles each way on 66 every day in my heavy armored up JK and average around 15mpg including terrible 66 traffic. On the way to Flagpole with the caravan staying at 60-65mph I managed to get it up to 19-20mpg which I was surprised by


Title: Re: Another gas mileage thread
Post by: sirjames186 on June 12, 2018, 03:09:37 PM
I'm not sure what it is, but I always get incredible gas mileage from Haymarket to Harrisonburg. Maybe it's the convoy? All those jeeps clearing the way. I've been in convoys that do 70mph the whole way too.

Normally I get 12mpg around town and 15 or 16 highway but last year at the fall ride I hit 21mpg from sheetz to sheetz.


Title: Re: Another gas mileage thread
Post by: RattleTrap55 on June 12, 2018, 03:16:52 PM

No wait.  I think I may have stopped for gas, some dinner, and maybe watched a movie in Mt. Jackson then took off again.

Watched a movie, REALLY? I am not that slow, am I?


Title: Re: Another gas mileage thread
Post by: 94JeepYJ on June 12, 2018, 09:18:33 PM
The lead guy got 12, everybody else got 20.  Somebody got the short end of that one...

In reality though, a lot of that trip is down hill.  Being a JMU grad, Iíve made that trip a lot and always get much better gas mileage there than back.  You should have tracked the return trip.


Title: Re: Another gas mileage thread
Post by: JeepsterCJ on June 12, 2018, 09:21:09 PM
My 84 CJ with 33's, 4speed trans, 3.54 gears and a 4.2L with a Motorcraft 2150 gets about 12- 13mpg.
It really depends on how I drive it.


Title: Re: Another gas mileage thread
Post by: Gr8Dain on June 13, 2018, 05:15:44 AM
Seeing as I have a 4.2l (258) with Offy intake and a holley 4 barrel carb, I donít usually talk mpg. But .... the best I have gotten was 15.x mpg. I hover around 11 or so. Sometimes 9.

So, maybe not the best choice for a DD into DC everyday. But I enjoy driving it too much.


Title: Re: Another gas mileage thread
Post by: RFH_98TJ on June 13, 2018, 06:56:14 AM
No wait.  I think I may have stopped for gas, some dinner, and maybe watched a movie in Mt. Jackson then took off again.
Watched a movie, REALLY? I am not that slow, am I?

Sorry, just had to do it.  :b


Title: Re: Another gas mileage thread
Post by: Davetopay on June 13, 2018, 07:50:04 AM
It's amazing how much of a difference slowing down can make in these less than aerodynamic boxes.. I regularly got 16mpg out of my 4 banger/33s when it was on the road, but slowing down to 60 would bring it up into the low twenties...

Never cared enough about mileage to keep it down to 60 for long :D

YUP. The LJ was getting 16-18 on a regular basis for longer trips on open highway. 33's, 4.10s, AUTO, winch, bumpers, tire carrier, skids, tools, spare DS, spare front shafts, heavy buns RK control arms, JKS track bar, magnaflow high flow cats and head pipe, and an MBRP catback. Scaled around 4300#. To make that number I'd set the cruise at about 60-65 and just let it eat. Around ton if I didn't act like a hooligan, I'd get 12. Bump up the speed to 70+ and I got 13-14. Add a head wind on I81 and set the cruise at 72? I'd be lucky to get 10.


Title: Re: Re: Another gas mileage thread
Post by: sirjames186 on June 13, 2018, 08:54:34 AM
It's amazing how much of a difference slowing down can make in these less than aerodynamic boxes.. I regularly got 16mpg out of my 4 banger/33s when it was on the road, but slowing down to 60 would bring it up into the low twenties...

Never cared enough about mileage to keep it down to 60 for long :D

YUP. The LJ was getting 16-18 on a regular basis for longer trips on open highway. 33's, 4.10s, AUTO, winch, bumpers, tire carrier, skids, tools, spare DS, spare front shafts, heavy buns RK control arms, JKS track bar, magnaflow high flow cats and head pipe, and an MBRP catback. Scaled around 4300#. To make that number I'd set the cruise at about 60-65 and just let it eat. Around ton if I didn't act like a hooligan, I'd get 12. Bump up the speed to 70+ and I got 13-14. Add a head wind on I81 and set the cruise at 72? I'd be lucky to get 10.
Can confirm (although I have 4.88 gears in my LJ). It seems to like 50-65mph, and 70 is ok, but it's amazing how much more it drinks if you're even a smidge over 70.


Title: Re: Another gas mileage thread
Post by: R3 on June 22, 2018, 08:48:17 AM
My little red lego block can see 20.+ mpg on a long run  at 55, drops to 19 at 60 and less at 65-70( 16-17)
Running 4.88 and BFG 37 with a spanish gear box. the sweet spot on my set up is 60mph.

Stop and go  traffic is  great.... drops to 14 or so depending on how long I get stuck  with 1.5 million of my closest friends

R3


Title: Re: Another gas mileage thread
Post by: RFH_98TJ on June 22, 2018, 09:46:37 AM
Old habits die hard they say.  I guess I haven't really slowed down yet and a lot of it was in traffic too.  Yesterday's fill up was 15.6 gallons at 186 miles.  11.9 mpg.   :pat

At least I'm not driving a minivan.