Fuel Mileage

[budojeepr]

Last weekend I took the diesel Wagoneer on a 170-mile trip, some mountain two-laner (up and down, elevation change ~5300 feet) at 50-65mph, some dirt road at 15-35mph, some flat highway at 65-75mph.

Got 18.36mpg.

[fulsizjeep]

Our AZ trip so far: we are getting 14.24 mpg with a stock 401 w/4350 carb, T400, QT, 3.07 gears and 31s tuned for 7000 feet. She rolled over 100K between Kayenta and Tuba City coming down. We are pretty happy with that. We have seen 87 octane gas for $1.89 down here too.

[mimmp]

Last weekend I took the diesel Wagoneer on a 170-mile trip, some mountain two-laner (up and down, elevation change ~5300 feet) at 50-65mph, some dirt road at 15-35mph, some flat highway at 65-75mph.

Got 18.36mpg.
It's a shame that the new diesel fuel is so much more expensive than gas. I have been thinking about switching, more for the project than the savings, but I've decided against it because it would cost more to drive the Waggy than it does now. For example, this morning I filled up at $1.79, diesel was $2.97. I've been averaging 12.5 mpg for a couple months; you got 18.36 ( which is admirable). It costs me 13.8 cents per mile with gas, but (at your mileage) it would cost 16.17 cents per mile. Now, I know that for the most part that's only $5 or $6 a week difference for me, but I need to think about it for a while.

I may still take it on as a project, but it's on the back burner for now. (New Katzkins are on the front burner.)

[fulsizjeep]

The return trip from AZ was 12.7 mpg average. It is all uphill from Phoenix to Flagstaff and a lot of hill climbing for the rest of the trip too. I am happy with that out of a 401.

[iluvnos]

I get 9 mpg in the city and 25 on the highway* who knew?




* I draft behind 18 wheelers a lot LOL

[getbentfab]

I get 11 mpg on propane.

[Chris P.]

I got 14.8 on a 100 mile interstate run today going 70-75 mph.

360-T18 with 3.54 gears and 31 in tires. A little more TBI tuning may get me over 15.

[peej07]

Just bought it first run 9.6 mpg, scary! Well time to start with the basics, air cleaner and such.

[duncanstives]

I think I average 7-10... I drive with a REALLY heavy foot though... with my jeep you can be pretty sure that if the ires arn't squealing either:
A: I'm not in it
B: Its broken. This is the case now... I think the accelerator pump is still not right because it dies if you stomp on the gas... You have to give it gas gradually.

[2ToneBluJ10]

In 1993 I got 21 mpg :dancingbanana: on a trip from New Bern,NC to Williamsport,PA via Delaware Water Gap, NJ about 750 miles, and fuel tank wasn't cracked then it finally cracked in 1997. Haven't checked it for years until I replaced the tank with one of the rare ones without cracks in 2007, rechecked then and it was getting 15 mpg combined city/hwy. Thats with the stock PITA Carter BBD after rebuilds and tune-ups and I mostly keep my foot out of it.......mostly! :D But it is a 258 I6 and I do get on it occasionally.

[loganvilledude]

When I bought my '89' Wagon last weekend I drove it home and the trip was almost 150 miles. I filled up before I left town and filled up when I got home. I drove 70mph on I-20 and she got 12.6MPG. You can't trust the electronic read out so the only way to truly figure your mileage is by calculating mileage on the odometer and the gallon amount you put in. I guess this is not so bad running on "33s"'.

Of course at the end of the day I bought the Jeep to have fun, not to worry about the gas mileage!

[Mr Haney]

In 1988 I had a 1980 Grand Wagoneer 360. We drove from southern Indiana to Florida and all over there and back home. I drove over 2000 miles on that trip and averaged 13.5 mpg for the entire mileage. I think gas was around 70 cents or so. I felt like I was king of the road in that 40,000 mile car. I have never been so proud to drive anything before or since. I miss that feeling- on top of the world! I felt like I HAD ARRIVED!MR. HANEY

[AnnieL]

I increased my mileage about 15% using my "secret juice." Once my new carb is installed, I'm sure she'll be doing that well again. I can't wait to get that carb on there, but got slowed waaaay down by a nasty visit from the flu fairy. :mad: (I was up to 16.5)

[newtojeeps]

I increased my mileage about 15% using my "secret juice." Once my new carb is installed, I'm sure she'll be doing that well again. I can't wait to get that carb on there, but got slowed waaaay down by a nasty visit from the flu fairy. :mad: (I was up to 16.5)

Secret Juice? Does this require the use of a big copper pot and coiled tube?
:D

[Chris P.]

Drove ~140 miles today in a mixture of city and highway in the J10 and averaged 16.6 mpg!

[gte901m]

Drove ~140 miles today in a mixture of city and highway in the J10 and averaged 16.6 mpg!

Was that in your junkyard fuel injected rig?

[Carleysjeep]

I get 12 on highway. Never checked it in town, but when the gas guage reads 1/4 you better find a gas station because it is empty. Don't ask me how I know that.

[lost1]

see, I have the opposite problem. At full tank I only read 3/4 tank and at empty I still have a quarter tank waiting for me. I live by the old rule 'Take care of the top half, and the bottom half takes care of itself.' though. I get between 9-11 mpg depending on driving conditions.

[Chris P.]

Was that in your junkyard fuel injected rig?

Yes. I'm aiming for 17 or 18 with some more tuning, but I'm not sure that is possible without overdrive.

[UnkleMunky]

[quote=lost1]see, I have the opposite problem. At full tank I only read 3/4 tank and at empty I still have a quarter tank waiting for me.[quote]

Exactly how my '80 J10 reads...3/4 when it's full. My first FSJ....a '77 Cherokee would read about 7/8 when it was full. I just got used to it.....making sure to get gas before it hit bottom. With my last few Jeeps, I've gotten so used to using my Post-It note fuel gauge and do my best to fill up every time I get gas, that I just glance at that more often than the actual gauge (and have just kept this up with the '80 as well). I have never run out of gas that way!

Still getting 16+ with the '78 (258) as of the other day, but seem to be averaging about 10-12 with the '80 (360)...and that's after TFI'ing the thing. So, even at 10mpg, I should be able to get around 200 miles on a full tank, so I try to fill up between 150-200 if at all possible. Can go further on the '78, of course, but still aim for the same.....better safe than sorry.

[Chris P.]

Just drove the ~140 miles back to Tech this afternoon and filled up a 100 miles. I calculated 17.4 mpg:eek:. I'm not trying to brag, but I am really stoked! I wasn't sure if TBI was going to be worth the trouble over a well tuned carb, but now I am glad I did the conversion.

[gte901m]

Chris P, that is awesome. I've been reading up on the tbi conversion. Doesn't look too bad, except for the tuning / chip burning aspect. I've been reading all the info on the bender planet forum. Is your 360 stock w/ tbi? What size tires? Manual trans?

[Chris P.]

Its stock except for the 8600 cam and performer intake.

Yes, T-18 manual, 3.54 rear end and 31 in tires.

Tuning can be confusing at first, but I actually enjoy it. I've been using TunerPro with the 7747-mine.xdf

I've been reading a lot on thirdgen.org about manually editing the hex code and patches. A lot more can be done with the chevy ECM than most people realize.

[WagonManiac]

My last FSJ was a 69 Wagoneer with a 71 Buick 455/Turbo 400/Dana 20/3.73 R&Ps/Dana 44 frt-GM 12 bolt rear & 29" tall tires. It didn't seem to matter how I drove or whether it was empty or full of camping gear, it got 12 mpg!
Sure wish I still owned it!

[Eiffelxx]

According to my GPS and gauge, I am getting 8 all around..But had a carb/vac issue...Hoping for 12's soon.

[jaber]

I feel fortunate to be in the lower 10%. The wifes is getting an average of 17.5 according to the last 2 fill ups. Rebuilt 360, RV cam and fuel injection on 31"ers and 2.72 gears and auto trans.

[vintagetrks]

I'm getting in the 12 to 15 mpg range but will better know after I run the rig more often. Took it on a run last weekend and it did alot better than I anticipated.

[gte901m]

With a factory motorcraft 4 barrel I was getting 11mpg.

So far with my junkyard tbi, I'm up to 14.5, and I'm still a little rich.

I have 3.73 gears and 30" tires, so I'm taching around 2,400 rpm at 55mph, which doesn't help. Slightly larger tires may help :) .

edit: forgot to mention mileage was measured with a gps - you can't trust the factory odometer....

[67Wagoneer]

17-18 on the highway, probably around 14 in town. A lot better than the 84 GW I used to have, that thing would never get any better than around 12.

The older Kaiser wags, when properly carbureted and de-smogged aren't bad. My '68 used to get decent mileage too.

[DEMIGOD]

On my most recent trip out on the interstate, I was able to squeeze 12.4 MPG. I was getting around 8 or so.:eek:

[brubakes]

Last tank fill up was 9.8 mpg.

[Mikel]

Last tank was 25.2MPG. And that was carrying 1200 lbs in the bed most of the time :)

How ironic that my FSJ gets better mileage than my '97 Riviera :rolleyes:

[brubakes]

Last tank was 25.2MPG. And that was carrying 1200 lbs in the bed most of the time :)

How ironic that my FSJ gets better mileage than my '97 Riviera :rolleyes:

I'm jealous.

[halftrac]

I think the last time I figured out my mileage was avg of 17mpg highway and in town. Most was "country road" driving, with plenty of tight curves. All this with a 258/4spd.

[brubakes]

I guess I'm doing something wrong then, because I know I should be getting more then 9.8.

[sappy76]

I guess I'm doing something wrong then, because I know I should be getting more then 9.8.
I just got 9.8 yesterday, up from 9.5. I just swapped chips in my Howell system and moved my timing to 10 degrees. I just keep playing games trying to find 17mpg. (Actually I average 20 mpg. I drive my FSJ (10mpg) 1/2 time and my Miata (30 mpg) the other 1/2.)

[gte901m]

I just got 9.8 yesterday, up from 9.5. I just swapped chips in my Howell system and moved my timing to 10 degrees. I just keep playing games trying to find 17mpg. (Actually I average 20 mpg. I drive my FSJ (10mpg) 1/2 time and my Miata (30 mpg) the other 1/2.)

Its very unlikely you will get to 17mpg by just swapping chips. You really need the ability to datalog and burn your own chips, specific to your engine / trans / tire combo. Just my .02

[sappy76]

I doubt I'll ever get above 12.

[crbour]

on a fresh "stock" drivetrain rebuild I am getting 10-12 in town, 14-17 at 55mph, and about 12-14 on Interstate @ 70mph..

[x6xdemonx6x]

does ft per gallon count?

[Cappicaper]

A wise man with a vast car collection once told me "I never check the mileage in a car I like."

I have been living that moto every since.

[CJ the noisemaker]

does ft per gallon count? :thumbsup:


I average 60MPG. Observe: http://www.youtube.com/watch?v=nJcIpJuJcv0

[Woody the Danger Wagon]

6.75 MPG over the last several months. Of course, that's on 35's. Anybody care to calculate the actual? Me neither.

[Songman]

Between 7 and 8 around town. I don't take it anywhere on the interstate so that don't figure in. The very few times I towed my boat or a trailer with it, mileage dropped to about 4mpg.

I would sure love to know how these guys are getting into the high teens.

[TJR]

I typically get about 12 to 13 all the time. In town or highway, doesn't seem to make much difference. could be much worse as you all know.

Its a 258 4spd

[Wagoneer622]

Hey Folks! It has been a while since I have been here. Just haven't had the time with finishing the college degree and such. Last time I had my 87 Wagoneer on the road before I had to put it away I was getting around 12-14 around town and about 16 on the highway. Stock 360 without any pollution equipment, 727 trans, and NP229 on stock sized tires. I hated watching that Jeep sit and rot away.

[CJ the noisemaker]

I ran my waggy out of gas today, estimated around 18 MPG. That is after I replaced the spark plugs, air, and fuel filter.

[Tatsadasayago]

I ran my waggy out of gas today, estimated around 18 MPG. That is after I replaced the spark plugs, air, and fuel filter.
WooHooo!

That's impressive!

[Serious Johnson]

I just got 9.8 yesterday, up from 9.5. I just swapped chips in my Howell system and moved my timing to 10 degrees. I just keep playing games trying to find 17mpg. (Actually I average 20 mpg. I drive my FSJ (10mpg) 1/2 time and my Miata (30 mpg) the other 1/2.)

My li'l hotrod Miata gets around 40 MPG summer and 36 winter, driving it like a flippin' maniac. Haven't quite broken 50 MPG yet, but might if I put the top up (note that this is at altitudes never dropping below 7,000', which makes a difference -- sea-level numbers are a good 20% lower).

The old Waggin'ear started dropping down to about 13 MPG on country roads and running like shiite. Turns out it had a broken valve spring, couple of bent pushrods and a buggered head gasket. Hope to be back in the saddle with a 20 MPG strong 360 as soon as I can push snow aside and twiddle wrenches.

S.J.

[anst2184]

I got 12.3 on my last tank. Could be better if I wasn't at sea level?

[Serious Johnson]

I got 12.3 on my last tank. Could be better if I wasn't at sea level?

"Could" be, but won't necessarily be. Any engine behaves as if it's smaller as altitude increases because of reduced air density. This of course results in reduced power and the potential for increased fuel economy. With a carbureted engine you'd have to manually change the carb jets and ignition timing to optimize for a specific altitude -- impractical if you live at 300' and drive over 9,000' passes. Electronic fuel injection with spark control handles it dynamically, but still with unavoidable power loss at altitude. The power loss, however, will be far less than with an unadjusted carbureted engine.

First time I took my completely stock '83 Wagoneer from sea level to 12,000' the resultant very rich mixture first made it a dog on the slopes, and pretty quickly buggered the catalytic converter. After that, it felt like it had about 25 HP and the thing was getting under 2 MPG. Next time I tried it, sans cat, I swapped jets (actually the whole carb) advanced spark at 7,000', and that worked sort of decently. I left the high-altitude carb on almost all the way back down to sea level, changing just spark advance. The thing drove progressively worse and eventually overheated.

Converting to EFI pretty much made the Jeep work better at any altitude. Power loss up high is now not especially noticeable unless I'm towing something big. But I do notice when going back east that the old rig feels extra sprightly. Fuel mileage increase from sea level to around 8,000' seems to be in the 15-20% range.

S.J.

[mike12]

12 town 16 hw its a j10 w a 4 speed:drivin: mike 12

[Etcetera]

I drove 67 miles on 5 gallons of gas. Put 5 gallons in it while 100 % empty, and ran it out again. 4350 on tired 360, desmogged. No tuning yet. Only had it a couple weeks. It has a part time kit on it, not sure if it's overdrive or not. Stock sized tires.

One thing that can make a difference on high mileage rigs is the condition of the wheel bearings.

I'm torn between tinkering with this engine or just keeping it going. Ultimately I'd like to do a 4bt swap.

If anyone wants to feel like you get great mileage with your FSJ, you can borrow my 89 GMC Crew Cab Dually with Big block (for sale btw) and no overdrive :banghead: for a couple weeks. Everything is relative.

[Songman]

I don't know what is going on with my 90 GW. It normally gets around 7-8mpg. I was about to upgrade from the stock 2 barrel carb and intake to a stock 4 barrel carb and intake that I took from a 74 wagoneer. Before I could get it done I bought the other GW and got the deal to take my 90 to Edelbrock for the headers. So I put what few things I had taken off back on the engine... Mainly just the air filter housing and re-plugging the hoses and lines.

When I left to go to Edelbrock yesterday I filled up with premium gas at costco. I figured it would be an extra $4 for the tankful and I might get a little better mileage. I was amazed when I got to Edelbrock. Almost 130 miles and I had only used 3/8s of a tank. Depending on exactly how many gallons it used, that converts to between 18-20mpg. Of course, I drove between 55-60 and tried to keep my foot out of it. But I did drive through a 4000 ft mountain range for about 35 miles too.

I can't explain it. Surely just using premium couldn't make that big a difference.

[dirty Bakers]

We Are getting 17.4 on the highway

[lost1]

@ Songman, it might be a topic of hot discussion, but all I've ever heard of premium gas doing is burning hotter, thus helping get rid of some of the crud building up in the engine.

so, you took a bunch of extras off, then wound up putting most or all of them back on? Was there any cleaning or rerouting of lines involved?

And, just to be s stinker, is it possible your gas guage hates you all of a sudden and is giving false info?

Hey it happened to me...:rolleyes:

But, if you're really stumped, you can always just loan it to me, and I'll test it out for ya.:thumbsup:;)

As for my rig, its doing better mileage wise with the newer engine, but I've been too chicken to do any real figuring.

[Songman]

I actually never got much farther than taking the air cleaner off. I don't think I changed anything of consequence. I know my Cadillac goes from about 11mpg up to about 18 just from using premium. But it was built for premium, the GW wasn't.

I don't want to think the gauge went wrong all of a sudden. It would be running on fumes at this point if it is. I don't know what the deal is but I am going to keep my fingers crossed! Haha

[smogdredd]

Once on Ca 99 I got 17.5 but due to shutoff variation at different stations this was probably a fluke. The other possibility is that I found the happy spot and stayed in it for 200 miles at 70 mph.

[M4203]

Must win lotto, must install 4BT diesel.:)

[AMC-J/20]

When driving a full sized Rig of any brand fuel mileage should be of a concern to you ;) Especially when you into a product that was dropped 88'-91' :thumbsup:


:D Ditch the Carburetors and go EFI :thumbsup: I'd say buy my K2500 Diesel it averages 19-21mpg over the tank of fuel :D it'll tow 9,000LB's behind it or haul 3,000LB's on board :thumbsup:


Mike

[Serious Johnson]

When driving a full sized Rig of any brand fuel mileage should be of a concern to you ;) Especially when you into a product that was dropped 88'-91' :thumbsup:


:D Ditch the Carburetors and go EFI :thumbsup: I'd say buy my K2500 Diesel it averages 19-21mpg over the tank of fuel :D it'll tow 9,000LB's behind it or haul 3,000LB's on board :thumbsup:


Mike

My Dear Ex's '06 F250 extended cab long beb 4x4 diesel with a slushbox got approximately the same fuel mileage as my Wagoneer -- 15-20, and diesel costs more.It could haul a good bit more than the Wag though.

S.J.

[AMC-J/20]

:D yup that it dose, but most swap these 6.5's into there FSJ's to increase the fuel mileage and workability :thumbsup:

:cool: I'm offering up a perfectly good truck no building need just turn key and tow ;) . . . Its either sell it or become homeless I'd rather see it go then me go :thumbsup:


Mike

[bijna]

After doing the TFI swap and installing an electric fuel pump, my swagoneer went from 7-8mpg to 12.25mpg. This must not seem like much of an improvement to most people because whenever I tell them I'm getting 12mpg now all they say is OMG that's horrible. Can't wait to see what happens when I get the exhaust leak fixed and all the emissions smog stuff off!

[crazy8s]

I'm getting between 10 and 11 pretty consistantly and thats with a leaky warn out carb, so I'm pretty happy. Stock size tires, no lift.

[twmattox]

With cold weather, I noticed my choke was not adjusted properly. Corrected the issue, and took a nice long trip 75% highway (speed of 70mph)...15 mpg. This was nearly a 2 mpg improvement over the incorrectly adjusted choke...

[austinaubinoe]

After doing the TFI swap and installing an electric fuel pump, my swagoneer went from 7-8mpg to 12.25mpg. This must not seem like much of an improvement to most people because whenever I tell them I'm getting 12mpg now all they say is OMG that's horrible. Can't wait to see what happens when I get the exhaust leak fixed and all the emissions smog stuff off!

HAHAHA I was talking to someone the other day and they asked me what my MPG's were. I told them 9 average, 13 if I drive like a grandma and there jaw dropped!

Then they basically asked me why I dont drive a prius and I didnt have an answer :thumbsup:

[Woody Mammoth]

Then they basically asked me why I dont drive a prius and I didnt have an answer :thumbsup:

Know the feeling, I got '91 GW and '07 Suburban that question had been raised few times. I politely answered "They are not my daily driver so I don't care. What I care is able to carry 7 passenger in my Burb, and both of my vehicles are capable of towing the camper I own. Your family unit is not same as mine and your vacation outings are not same as mine." This kind of question was usually asked by my friends that are single or DINKs. I do own 3 bicycles and 8 bicycles in the household, so that'll make up for the MPGs. Oh! yeah.. this past summer, I got a taste of driving on the beach with my Burb down at the outer banks. Saw a poor little Honda element tried to be a 4WD vehicle and failed, never got passed beyond the driveway into the beach. Now I'll dare any Prius to try that too...:fsj: than again, Prius owners would have walk from the parking lot to the beach on their Birkenstocks to save more gas..:D

[SkylinePCG]

Then they basically asked me why I dont drive a prius and I didnt have an answer :thumbsup:

Some people like having $300+/month car payments, increased insurance costs, increased maintenance costs, more expensive parts, and put up with driving a disposable vehicle just to spend less on fuel.

Personally, I find the sales pitch to be a bit weak!

[AMC-J/20]

:D any full sized truck getting in excess of 12.5MPG Is way to weak for my liking :thumbsup:
:D Most of my trucks get 6-9mpg and will tow in Excess of their GVW/GCW's :thumbsup: without slowing down :drivin:

The MJ gets 14-16mpg and dose get a bit doggy above its GVW but im fixing that problem ;)

Mike

[sappy76]

I pulled my fulltime Quadratrac and dropped in a MM Part Time 16% OD. I drove all summer this way and didn't see any noticeable difference in mpg. I'm sitting at 10 mpg no matter what I do. (I drive it like a truck, not a moped.)

I'm swapping back to the fulltime Quadratrac. I built the truck for winter driving and to use as my hunting/fishing rig. I'll continue to use the Chief as my daily driver from Nov-March and jump in the Miata for the summer. (Hard to believe but I have 3x the amount of money sunk in the Jeep than I do in the Miata.)

[dblankenbaker]

10.6 mpg on my first tank! :thumbsup:

[AMC-J/20]

:D 10.6 that is awesome :thumbsup: none of my full sized truck pull that high :D

Mike

[Camo-5]

13.27-13.43 :D In my 1985 Waggy

I just checked it via gps for the first time on a 600 mile round trip. My gas gauge isn't working, so I felt it was kinda important to know what kind of mileage I was getting. That running out of gas thing in Northern Michigan in the winter stinks.

I was suprised it was getting this good. I'm running 33s, factory 2.83 gears (ouch), 727 trans, Jasper 360 2V with about 50K on it. Running between 71 and 74 mph (gps of course).

Oh yeah, if you are wondering, it's a gutless pig off the line.

[OBXcited]

My holiday driving astonished me! Finished a 500-mile roundtrip (miracle #1) and kept track.

Keeping up with I-95 traffic at 75-80mph for 172 miles, I got 13.7 MPG.

Slowing down on the return leg while following my wife at 65mph, I got 21.7 MPG!!

stock 1984 GW
360 cid w/ 2bbl
premium gas
5w40 Mobil1 Turbo Diesel oil
unknown gears
wasn't drafting tractor trailers

[Gymmie J10]

I was getting on a good day, coasting downhill both ways I was getting about 2 miles per gallon, yes that's 2, as in TWO. This is a mixer of city and highway driving.

Tuned it up, got about 3-4 miles pg then.

Replaced the Distributor Assembly, and changed to duel exhaust with flowmasters and I'm now getting in the range of 8-10 mpg.
Not positive yet as this is only my second day driving with the flowies on.
One thing for sure....it sure sounds nice when I get on that 360 now....:)

Just wish I could find better quality gas.....she pings like I've got ball bearings under the hood.

[ks114]

When I first got mt 88 Wagoneer, I made 8.5.http://www.ifsja.org/forums/vb/images/icons/icon8.gif
I did the TFI upgrade (Juicebox 8), new plugs, set the timing, replaced suspect vac. lines, cto switches and EGR valve. It now makes 12.5 consistently combined city and hiway MPG.http://www.ifsja.org/forums/vb/images/icons/icon10.gif

[FSJunkie]

I don't want to know what it is. :D I'm guessing around 13 overall. I can squeeze 17 out of her on the highway rolling 75. It seems to get more minutes per gallon offroad than on road, seriously.

[Thumper168]

Checked mine today, it was a scary 9.8 mpg.. This proved to me the big block will be going in sooner than I planned.

[old faithful]

What are you guys getting on average for fuel mileage. I'm just wondering what the norm is. I've done some searching and didn't see a thread like this. let me know and if you want, tell us about your setup so we can get an idea of what we are getting into. :fsj: I get about 13-14 and sometimes a little more if I keep my speed down. I also installed a vacum gauge that helps me stay off the pedal so heavy. I keep it tuned regular and the tires pumped up.

[FSJ_Daniel]

i get about 8-10 on backroads, and about 8 on highway and wheeling in the woods i dont even wanna know:banghead: but this is with a 500ci motor dropped in old blue:thumbsup:

[1jeep4me]

I can see it, keep speeds steady at 60-65 produces very good economy.

What happens is when our 3 speed transmissions get mixed up with 331 gear or better, our mileage goes to doggy doo


My holiday driving astonished me! Finished a 500-mile roundtrip (miracle #1) and kept track.

Keeping up with I-95 traffic at 75-80mph for 172 miles, I got 13.7 MPG.

Slowing down on the return leg while following my wife at 65mph, I got 21.7 MPG!!

stock 1984 GW
360 cid w/ 2bbl
premium gas
5w40 Mobil1 Turbo Diesel oil
unknown gears
wasn't drafting tractor trailers

[86gwrhino]

gettin round 16 highway and 9 in town with the 350 tbi and 2.73 gears

[newwagwheeler]

OK... isn't it just easer to calculate gas stations per week than miles per gallon. LOL Actually I am seeing 11-13. Can't really count highway b/c it is mostly mountains. I would really like to know how some of the people in this thread are getting 16 and 20 plus... I understand downhill, but eventually you have to come back....right?

[jeepjseries]

OK... isn't it just easer to calculate gas stations per week than miles per gallon. LOL Actually I am seeing 11-13. Can't really count highway b/c it is mostly mountains. I would really like to know how some of the people in this thread are getting 16 and 20 plus... I understand downhill, but eventually you have to come back....right?


A few are running GM drive trains with overdrive transmissions and others turbo diesels and such. Some say with a 4BT Cummins and a overdrive transmission,proper gearing 30 M.P.G is possible in a FSJ.:D

[shakari]

I don't understand how it seems to vary so much.

I keep a very strict log of (all) exact costs of mine and admittedly drive virtually on tickover a lot of the time here but mine has an Edelbrock carb, Cobra thru flo exhausts and heavy toolbox & recovery kit in the back, yet I get 5-6 kilometres to the litre and unless I'm having a senior moment (which ain't impossible) that translates to 20 - 24 per USG?

[82FSJ]

getting about 13mpg when I drive like an old granny. Running 360 on LPG and 31's on stock ratios.

1982 Cherokee.

[mackey84]

getting about 13mpg when I drive like an old granny. Running 360 on LPG and 31's on stock ratios.

1982 Cherokee.

What do you pay per gallon of propane? With gas prices as they are would it be worth a conversion?

Does economy drop a bit with propane? But if $/gal is lower would you actually be money ahead?

[bruner1981jpce]

I've got a 258 with a T-176 and got exactly 15 MPG before I did the Nutter bypass. I'm expecting more with the bypass and probably a bit more once I swap out my Carter BBD for a Motorcraft 2100

[bolognablake]

Wow, I'm planning on buying a FSJ very soon and I'm glad it wont be a daily driver. I didn't know the mileage could be so poor.

I'm getting better mileage than a lot of you guys in my V10 F250 on 35's!

[wonderwag]

300 mile highway trip 15.5 mpg with a 1600lb boat behind, a canoe on top and a cargo area full of gear. but I do have a 5.3 vortechttp://i983.photobucket.com/albums/ae316/wonderwag/0821111456a.jpg

[shakari]

What do you pay per gallon of propane? With gas prices as they are would it be worth a conversion?

Does economy drop a bit with propane? But if $/gal is lower would you actually be money ahead?

MPG & performance will drop slightly but service intervals more or less double. The engine should also run quieter & smoother on LPG.

[jobri478]

13.8 mpg 70% highway. (t18/d20)

came up from 11.5mpg (th400/ qt)

mc2150(converted to manual choke) 360 w/ 110xxx still working for 15 mpg!!! next step is mech + vac advance!

[18cherokee]

What do you pay per gallon of propane? With gas prices as they are would it be worth a conversion?

Does economy drop a bit with propane? But if $/gal is lower would you actually be money ahead?

us$2.45 per gallon.
economy drops about 20%

i considered removing the kit (dual fuel) from my rig but then i thought "hang on, i'm going to remove something that people pay $2k to put on"? im actually glad that i decided to leave the kit on the truck the way things are going - increases range too if anything.

[serehill]

It should have been: How much do you really get in Gas milage not fantasize.

[dan01ster]

'82 J20 with Holley ProJection, TF727 w/ 3.73, GVW is 8400lbs. At 50mph she gets 18 mpg ( US gl)...with the tale gate up. That was running on factory 9.50 x 16.5 radials...not a wide tire.

[the original Honcho]

We used to have a '78 Cherokee Chief that war originally a 4v but right away we changed to a 2v intake and just the right carb... mixed driving (55mph highway/city/off-roading) averaged right under 25 mpg. Sadly this Jeep was washed away in a flood in '06:(

My Honcho was getting around 15, unless I was hot rodding it in which case that would drop to about 12.

The '91 Grand is getting about 9:banghead:. Time to go to work and duplicate the Cherokee Chief setup...

[Mr Carts]

Hmm. 25MPG I am Mister economy and I dont get more than 12-15 mpg.
1980 Chief with 360 2V.

[jonygeorge]

I have a ford 460 in my wagoneer with NV4500 manual transmission, stock 2.73 gears and 33" wheels. Just got 16.7 mpg on trip from cedar city UT to Ogden UT. I only turn 1600 rpm's at 70mph.. Pretty good mpg for a 460!

[the original Honcho]

Hmm. 25MPG I am Mister economy and I dont get more than 12-15 mpg.
1980 Chief with 360 2V.

Run very far away from that 1980 carb! From my experience newer carbs suck for mileage. Ive got a lead on a nice motorcraft from a Maverick 302 that I am checking out tomorrow morning. Wish me luck.

[manimal]

This is weird...the last post shows a date of 4/14/12, but yet the title shows the last post was made today!?

[RWrightPhotog]

It moves up everytime someone votes.

[nc wagoneer]

I seriously think a "I don't wanna know" option is in order!!! Last time checked =<8 :eek: why do the fsj gods hate me??? :banghead:

[the original Honcho]

I seriously think a "I don't wanna know" option is in order!!! Last time checked =<8 :eek: why do the fsj gods hate me??? :banghead:

Work on the tuning!
if you dont have the experience find a good mechanic that you can pay and who doesnt mind showing you what he does. its a great way to learn!

[nc wagoneer]

I'm 13 and just getting in to fixing up the wag :thumbsup: it probably doesn't help the fuel mileage with a tired 360, quadratrac, a badly slipping th400, and is usually towing something lol :D when its on the farm and off-road we speak of gallons per mile :banghead: maybe it'll break 10 someday :thumbsup: or that elusive 15 :rolleyes: