Fuel Economy???

[CapelConcepts]

I was wondering how many people are building/planning there expedition vehicles with fuel economy in mind. Is there a call for a practical rig? I'm building a '91 YJ for a customer right now that is planned out as being very economical (relatively speaking). It's running a TBI 5.7 out of a '95 pick up, but he went with 3.55 gears, 33" tires, and an NV4500 Transmission. This combination should get him around 20mpg.....when the 350 gives up the ghost it's gonna get a Cummins 4BT!:jump:

I'm posing this question in the forum section that would generally have the worst average MPG to see how it (the MPG) affects opinions towards certain rigs. Do those darn rising gas price put a limit on the number of trips you're able to do, whereas if your rig got 20-40% better MPG you'd still be out having fun?

Thanks for any and all input!

[madizell]

I just buy gas when I need it. Too old to start riding a bicycle again.

If you can get 20mpg out of a Chevy 5.7, especially mated to the NV4500, you will be doing very well. I would expect more like 12 to 15 tops.

[JIMBO]

:roost: It doesn't affect me that much, I go UP to the Sierras for a week, every month (good weather) and going up for the trip, I get 15mpg, coming DOWN from the trip I get 20+++mpg and the total is usually 500miles +++



I was wondering how many people are building/planning there expedition vehicles with fuel economy in mind. Is there a call for a practical rig? I'm building a '91 YJ for a customer right now that is planned out as being very economical (relatively speaking). It's running a TBI 5.7 out of a '95 pick up, but he went with 3.55 gears, 33" tires, and an NV4500 Transmission. This combination should get him around 20mpg.....when the 350 gives up the ghost it's gonna get a Cummins 4BT!:jump:

I'm posing this question in the forum section that would generally have the worst average MPG to see how it (the MPG) affects opinions towards certain rigs. Do those darn rising gas price put a limit on the number of trips you're able to do, whereas if your rig got 20-40% better MPG you'd still be out having fun?

Thanks for any and all input!

I'm pulling a trailer and I use ONLY, (union 76 gas)

:rally_guys: :rally_guys: JIMBO

[charlieaarons]

Your chassis is geared perfectly for the 4BT: 1660 rpm @ 60mph in 5th gear. Probably a little too tall for the gas V8, except that it's an ultra light chassis.
Otherwise I'd comment that the 4BT is a bit too much motor for a Jeep chassis, a 2.8TGV would be better. That's the 2.8L version of the 2.5L 300Tdi motor used in Land Rovers till they went to the Td5. TLC (re-vaped old Land Cruisers) is using the 2.8TGV/NV4500 in their Icon vehicle.

Charlie

[02TahoeMD]

Although it is nice to get decent fuel economy, I have always fallen on the side of having more power than getting good gas mileage. My most recent trip, the day I crossed the Appalachians I got 13 MPG, and then was averaging 16 MPG per day afterwards. And considering the size of my truck, and the fact that I have all the aerodynamics of a cinder block, I wont complain about that.

[madizell]

Your chassis is geared perfectly for the 4BT: 1660 rpm @ 60mph in 5th gear. Probably a little too tall for the gas V8, except that it's an ultra light chassis.
Otherwise I'd comment that the 4BT is a bit too much motor for a Jeep chassis, a 2.8TGV would be better. That's the 2.8L version of the 2.5L 300Tdi motor used in Land Rovers till they went to the Td5. TLC (re-vaped old Land Cruisers) is using the 2.8TGV/NV4500 in their Icon vehicle.

Charlie

I personally don't think a 350 is too much motor for a Jeep, but only that the 350 TBI Chevy is not an economical motor. The NV4500 is a very wide ratio 5-speed. First is so low it is worthless on the street, so essentially you will have a 3-speed w/OD. The gap between 2nd and 3rd is too broad for most street use unless you have major torque available, otherwise there is a temptation to run 2nd up a bit more than you might otherwise just to get well into 3rd before shifting up. Not an economical mode. It is also extremely heavy, has more parasitic drag than most manual transmissions you will find in regular sized cars and trucks, and has an input shaft bearing whine that will drive you nuts, and which can only be corrected, if at all, by machining the bearing cover until you have taken up enough slack to pre-load the bearing enough that, when the transmission is hot, the bearing clearance will be correct. New Venture says it is just a noisy transmission and the input shaft bearing pre-load is fine as manufactured, so there is no data on which to rely in pre-loading the bearing or machining parts. I have had mine apart numerous times and the bearing track on the race shows contact only on about 50 or 60% of the race. That's not correct in my book, and the noise is still there. I have machined it twice, reduced noise by 50%, and I would machine off even more, but taking that monster out of the truck is not something you want to do at home.

[Chas Stricker]

Hey Charlie,
Don't you get about 20mpg with your Mog?
Chas

[CapelConcepts]

Although it is nice to get decent fuel economy, I have always fallen on the side of having more power than getting good gas mileage. My most recent trip, the day I crossed the Appalachians I got 13 MPG, and then was averaging 16 MPG per day afterwards. And considering the size of my truck, and the fact that I have all the aerodynamics of a cinder block, I wont complain about that.

It's kind of funny you mentioned the fact that you'd rather have the power than the economy. I used to work at Magnuson and we noticed that you could increase a vehicles mileage while increasing the power.....as long as you could resist the urge to floor it everywhere you went....which no, I can't! Anyways, the extra power allows you to pull a higher gear in most situations and keep the RPMs lower.

As for the NV4500 and the gearing, I've never noticed any issues with the NV...but then again, almost everyone one I've driven with has been behind a Cummins in a Dodge. Yes, the gearing is higher than normal, but the owner wants to cruise down the highway at a reasonable RPM....and as mentioned, it is a relatively light vehicle for this motor so that should help any power issues it may have.

Just to clear things up, I was curious as to how much planning of fuel efficiency goes into your average rig or how much of a concern it is. I'd really like to hear about the Mog getting 20mpg! That's awesome!

[cruiser guy]

With the price of fuel going up all the time, I think you'd be foolish not to consider economy.

My '82 BJ60 LandCruiser gets 30mpg if I'm easy on the throttle and about 20-25 if I'm not. It'll eventually make the difference about being able to afford to get out or not.

My next plan is running bio-diesel that I am able to produce from some local source that "big oil" and the speculators don't have a hand in so they can't jack the prices on me.

[masterplumber]

I'm one of those guys who actually needs a full size truck as I'm always hauling enough stuff for 4 to 50 people on our trips & also need to tow horse trailers etc.. I do think of economy a lot & am presently concerned that my Power Stroke has dropped to 12 - 13 mpg going down the road. in the old days this would have been terriffic for a 10k pound truck going through the Rockies but not good enough anymore. I suspect fuel injectors as all the electronics check out but I've also talked to others who have dropped mpg coinciding with the advent of ULSD that we have now. So if anyone comes up with a vehicle that can seat 5 - 6, haul 2000 - 3000 lbs in the bed, & tow 12,000 lbs while getting 30 mpg let me know. Oh yeh, it can't cost more than my 1st house - the price of trucks is completly out of line with the rate of inflation & the big three are still losing money - what's up with that?

[West Coast Mags]

Masterplumber,

It's funny that I stumbled on this post as I've been considering a 94-97 F350 Crewcab Powerstroke as an expedition chassis and was wondering where I could go to find out what type of mileage that truck would get. I formerly had a 2003 E550 17' box van, powerstroke, auto trans, 17,500 GVW and that got 14mpg whether it was loaded with pallets of wheels or empty. So I guess I was figuring a regular pick up would get 17-20mpg. MP what are your thoughts?

I've spoken to some of the dodge guys at work with lifted 4 door dodges, 35" tires, 4.56 gears with the Cummins and they say they get 21-22mpg all day long.

For my plans I need a crew cab, 4x4, diesel that gets around 20mpg, is it possible?

[CapelConcepts]

I'm one of those guys who actually needs a full size truck as I'm always hauling enough stuff for 4 to 50 people on our trips & also need to tow horse trailers etc.. I do think of economy a lot & am presently concerned that my Power Stroke has dropped to 12 - 13 mpg going down the road. in the old days this would have been terriffic for a 10k pound truck going through the Rockies but not good enough anymore. I suspect fuel injectors as all the electronics check out but I've also talked to others who have dropped mpg coinciding with the advent of ULSD that we have now. So if anyone comes up with a vehicle that can seat 5 - 6, haul 2000 - 3000 lbs in the bed, & tow 12,000 lbs while getting 30 mpg let me know. Oh yeh, it can't cost more than my 1st house - the price of trucks is completly out of line with the rate of inflation & the big three are still losing money - what's up with that?


I think there are a lot of guys in your situation that need a large truck on a daily, or close to it, basis. The ULSD is a very scary thing! The sulfur was the lubricant...what's doing the lubricating now? I how they (the government) didn't screw up one of are greatest and easiest ways at increasing fuel economy...Diesel! I'm not sure if you'd tried this out or not, but I've heard a half a quart of ATF in a tank of diesel is a good lubricant. Also, bio-diesel is supposed to have much better lubricating properties. Just some thoughts.

As for a rig that will hold 5-6, haul 2000-3000 lbs, tow 10000 lbs, and get 30 mpg how about 2 small European SUVs! I believe they have a couple of small SUV in Europe that are capable of half the load and all the mpg!

[masterplumber]

Replying to the above 2 posts. I used to get 17 - 19 mpg with a just a cap or topper on the bed, street biased tires & empty. When i put the Four Wheel pop up on & got more aggressive tires ( still the same height at 265\75-16) I dropped to about 15.5 for a long time & I could probably live with that. Right now I usually get 12 - 13 on the highway & 10 if I'm towing heavy (8000 lbs +). I have a friend with a 2001 F250 PS with a 6 speed manuel & on a trip last year with 3 guys, all our hunting gear & the meat from 3 elk we did average 20 -21 through the mountains - no trailer or camper though. I have heard from many people that own Dodges that they do acheive around 20 mpg but not towing or loaded heavy.

As for ATF I haven't tried it as I've heard mixxed reviews but I do get 1\2-1mpg better using Power Service diesel addative which is available even at Wal Mart.

I'm looking forward to seeing everyone else's ideas on this topic - there's no magic bullet as it takes torque & horepower to move weight but every little bit helps --- Doug

[Bella PSD]

Masterplumber,


I've spoken to some of the dodge guys at work with lifted 4 door dodges, 35" tires, 4.56 gears with the Cummins and they say they get 21-22mpg all day long.

For my plans I need a crew cab, 4x4, diesel that gets around 20mpg, is it possible?

On the first part about the 4 door lifted Dodge....I don't think they are not giving you real #'s on the MPG they get. Just what they "think" they get. Maybe they are getting 21-22 every day all day, but I very much doubt it. With a lifted 4 door (4 real doors) truck running 35’s, you can get 22 mpg but not every day.

Running empty and babying it all they way, you can easily get 22 plus out of a 7.3 lifted 4 door Ford. Any other time you are looking at around 19 MPG average unloaded and 17-17.5 MPG at best in the winter months. I have a 6 speed that does help by about 1 MPG. I added an empty over the cab camper and dropped to 18 MPG on the highway running 2000 rpm (70 mph).

Real word Ford 7.3 4 door example; I just went to the Outer Banks for a 2 week trip. Round trip average MPG was 17.43. This included about 120 miles off road in DEEP sand. Truck was well over 10,000 lbs at the start of the trip loaded up for the trip. This included a camper, water, 34 gal diesel, camping stuff, 2 dogs and 5 people. Highway speeds were 70-72 when I could and all other highways were 55. At the end we were down maybe 300-400 lbs (water and supplies).

Louie

[West Coast Mags]

Louie,

You've got pretty much the set up I'm working on. I'm planning to do a lifted crewcab with a Uhaul truck box on the back. Currently working on my M101 trailer with a conventional 8 lug trailer axle as well. I'll be running the same wheel/tire combo all the way around the truck trailer, trailer and spares.

Nice set up man!

[mrblond]

I have one of the 07 4 door Dodge CTD 4x4 lifted w/35's and my over head comp reads 19+ bit real world is more like 17.6 and this is about 50/50 hwy/city average.

I have done better on hwy of course but what I like is the over 600 mile range between fill ups and I have been told that the mpg might go up after break in.

[Bella PSD]

I have one of the 07 4 door Dodge CTD 4x4 lifted w/35's and my over head comp reads 19+ bit real world is more like 17.6 and this is about 50/50 hwy/city average.

I have done better on hwy of course but what I like is the over 600 mile range between fill ups and I have been told that the mpg might go up after break in.

mrblond,

Welcome to the Expo!!

My over head computer reads about .75-1 mpg high. The HP chip messes with it. The 600 mile range is nice when I am getting the 20 plus MPG, my tank holds about 33 stuffed to the top with diesel(short bed). I bet your MPG will go up as you get 50,000 on the clock. Thats when mine felt broken it.

Louie

[mrblond]

mrblond,

Welcome to the Expo!!

My over head computer reads about .75-1 mpg high. The HP chip messes with it. The 600 mile range is nice when I am getting the 20 plus MPG, my tank holds about 33 stuffed to the top with diesel(short bed). I bet your MPG will go up as you get 50,000 on the clock. Thats when mine felt broken it.

Louie

Thanks man, I originally lost about 1.5mpg after I put on the 35" toyos, they almost did'nt roll down hill w/o help. I did re-cal the speedo. After about two tanks and switching to synthetic I seemed to get almost all the mpg loss back.

Anyway, not sure if the mpg gain was maybe the tires smoothed out or the syn motor oil, or both? I have a little over 20K miles.

[02TahoeMD]

Something you may want to look into is finding someone that does dyno-tuning of your engine's PCM. I used a small company called Black Bear Tune in VA, who specializes in late-model GM engines. He adjusted for my Flowmasters, snorkel, my tires, and adjusted for my driving style, as he took a drive around town with me. He didnt charge me for updating once the snorkel and bigger tires were on it.

Anyway, paying him for the custom tune of my PCM was, I think, the best money I have spent on the engine / performance. It truly changed the performance of the truck, and even helped my fuel economy, which I can not complain about a 16 MPG average when I cruise at about 75 on the highway with frequent trips into 90 MPH + range for passing.

[Guinness44]

Our stock Cumins can get 20, but its more likely around 18. (we did up the tire one size, thats all). (Its an 02, quadcab, 4by, autotrans.)

DO NOT use tranny fluid in your diesel. There is plenty of lube additifs around. For sure read the label and DO NOT get any with alcohol.

[charlieaarons]

Hey Charlie,
Don't you get about 20mpg with your Mog?
Chas

On a 26000 lb vehicle? I think my 9mpg is good. It doesn't affect my decision making on travel plans.
I've read stories of people getting 7-8 mpg with 6.4L Powerstrokes with big campers on F450s (no towing!), which to me is shocking for a 12-13000 lb vehicle. A DieselStop user said he spend $6000 on fuel on a 8500 mile trip to Alaska and back. Figure it out.

Charlie

[wild1]

I like the modular approach to fuel economy, I can use the one that best suits my needs and gets the highest mpg. The Superduty V-10 hauls the house and everything else and gets 10 miles to the gallon. The LJ is great for exploring and makes a great trailer that will go about anywhere and gets 17 miles to the gallon. The TW200 is the secret weapon, at 80 miles to the gallon it's hard to remember when you last put gas in it.

[CapelConcepts]

I like the modular approach to fuel economy, I can use the one that best suits my needs and gets the highest mpg. The Superduty V-10 hauls the house and everything else and gets 10 miles to the gallon. The LJ is great for exploring and makes a great trailer that will go about anywhere and gets 17 miles to the gallon. The TW200 is the secret weapon, at 80 miles to the gallon it's hard to remember when you last put gas in it.

That is a great set up and an incredible pic to go with it! I like the "modular approach" you have there. I'm highly considering a BMW F800GS for some adventure rides...but they ONLY get 40-50 mpg, nowhere near your 80 mpg. ;) I think you're the first V-10 SD to chime in, how do you like it? If you're getting 10 mpg loaded I guess you aren't as far off the diesel numbers as I thought you'd be. We did some really cool supercharges for a company putting the V-10s into cop cars and running them on natural gas when I was at Magnuson. Unfortunately the conversion never took off. It was a neat set up though!

Guinness44, what's the reasoning behind not running ATF through a diesel?

[wild1]

The GS is hands down a better primary expedition bike then the TW, sort of like the Superduty to the LJ, but you can't haul a GS on the hitch so I guess the TW is as good as it gets. I ran a 96 F-350 diesel for 100,000 miles over 8 years. About half of those were with a total weight within a thousand pounds of the Superduty. I loved the diesel when it was twenty cents less then regular and delivered about 14 miles to the gallon fully loaded or 19 empty.
With the current cost of diesel in the US I much prefer the V-10,it's quiet,clean, and gas is available anywhere. I have found the V-10 more then adequate for the things that I have used it for.

[Bella PSD]

On a 26000 lb vehicle? I think my 9mpg is good. It doesn't affect my decision making on travel plans.
I've read stories of people getting 7-8 mpg with 6.4L Powerstrokes with big campers on F450s (no towing!), which to me is shocking for a 12-13000 lb vehicle. A DieselStop user said he spend $6000 on fuel on a 8500 mile trip to Alaska and back. Figure it out.

Charlie

That same trip with my Ford 7.3L (10,500 lbs) would be about $2,355.00 in fuel. Maybe I should just go and do the trip to prove it!:beer: I did the math on the $6,000 bill and it adds up to 7-8 mpg if he spent around $4.85 per gallon. Thats just real bad, no getting around that. I would think that something could be done to improve the MPG on his 6.4L?? I'm very happy with my 7.3L and will hang on to it for a long time!

Louie

[Chas Stricker]

Howdy Charlie,
I got back from a trip to Montana with our travel trailer and got 10.5mpg. I only went 55-60mph and thought overall it was good. $1,500 for fuel was still a cheap vacation. I don't have the power you guys have though.
Chas

[77blazerchalet]

Eeek. 31 gal tank for my Chalet with prices at $4/gal gives me the creeps. 1977 era 400 engine with a carb is 9-ish mpg? It's still not fully restored, so my vacation in the Ouray area last week is basically what I've done for the last 20 years, tent camping out of a nicely maneuverable hatchback that gets better than 32 mpg. My total gas bill was $164, but the car stayed basically parked four days.

Buying the Chalet two Marches ago didn't seem like a bad idea. However, I never have gotten used to the acres of Chevy hood out front, and gas prices won't retreat much. So I intend to sell it, and then come up with something with a shorter hood, more compact overall design, and newer engine (diesel/fuel injection) technology in order to aim for high teens or better mpg..... I mused about a 4x4 Westfalia-ized minivan in this thread (http://www.expeditionportal.com/forum/showthread.php?t=10162), maybe a custom Westfalia-style roof on a smaller SUV instead.......

[fisher205]

77blazerchalet, Do you know anybody that's put a Chalet on a diesel blazer? What fuel economy they got? That 6.2 has gotten a bad rap, but the guys I know that have set them up right are getting 22 to 24 in suburban's. I have been toying with this idea for a while.

I just got back from a 1700 mile road trip to Missoula and back with side trips to do a little fishing. My '94 Dodge 12V Cummins w?10' Alaskan Camper averaged about 14 mpg pulling a uhaul. Final tank was at a little over 15
( wind to the rear thru Wyoming). - Brad

[West Coast Mags]

I'm active on coloradok5.com and have read numerious accounts about folks with the M1009 CUCV Military blazers that keep them stock and but swap in a 700r4 over drive trans and set the tire diameter and gearing to equal 1900 rpm for whatever speed they typically drive and 28 seems to be the magic number. The military blazers were 15 more horsepower than the regular diesel blazers and that helps. They still sell regularly for $1000-2000 on the govt auction sites, but you have lots of paperwork, have a limited window when you can pick up the vehicle, can't work on it in the military lot, and never really know what you're getting into. In most parts of the country you can find folks that buy them as a hobby, have their own stock of spare parts, fix them up and make them driveable, then sell them for $2000-3000. That's the way to go, pay a little bit more but then know what your getting. Their on ebay and your local craigslist regularly, as I think more about this you can get running 6.2 diesels locally for $400 - $600 all the time, drop one of those in with the overdrive trans and mabye a modern transfer case out of a suburban into your blazer and enjoy. After having spent some time disassembling my chalet camper unit (now for sale as a whole or parts) I think it would be easier to buy a used diesel truck or suburban (diesel 2wd burbs are practially free) and swap the drive train in, rather than trying to transfer the camper to the other blazer. A few guys that know old chevy's could do the drivetrain swap in a weekend, or a week at most. As far as gas to diesel all you have to do is drop the tank, blow it and the lines out with compressed air, install a pair of inline fuel filters before the motor, and then about 3 wires and that's it. Since that body style of blazer had diesels in them you can buy motor mounts at any auto parts store and the transmissions bolt up the same, or just use them from the donor vehicle. Yeah, it would be pretty easy, I'd keep the chalet and do a diesel conversion, you could get it down for $1500-$2000 and though the camper is aerodynamically challenged could probably get in the low 20's easily instead of 9 with the gas motor.

[77blazerchalet]

...you know anybody that's put a Chalet on a diesel blazer? What fuel economy they got?.. - Brad
Brad, at least two of the members of our Yahoo forum are right in the process of the transfer of the Chalet shells to newer same body style diesel Blazers, and a third guy started but gave up on the idea. Meanwhile the creator of the Yahoo forum Doug W is an advocate of the swap idea as "metapoint" describes and will probably do that with his Chalet. Wish I could tell you the mpg specifics, but no one that I know of has completed their projects yet.

[Fireman78]

When I first switched from my Tacoma to Power Wagon, I was shocked at how much the gas mileage thing would affect me. I was getting about 17 in in my Taco, and heck, I was complaning about that. But then I went to the Power Wagon, disclamer-( I needed a full size for my side forestry buisness). I am now getting between 10-12 with my new beast. I miss the Taco, as it was a great exploration vehicle, but as far as all out, do anything, haul, tow, climb, crawl, carry, pull, ect.. nothing can beat the overall package I have put together with the PW. I honestly hate paying the $$ we are all paying, but now there is just no way I could ever go to a different vehicle. It does everything! I have cut back on other things to make up fo the gas thing, like....fewer trips to REI, Sportsman Warehouse, ect. Perhaps someday we can get gas $$ down to 2.50 a gallon, I could live with that!

[eugene]

I bought my truck early in 2005 when gas prices were just starting to go up so I did think about fuel economy. I have broke 20mpg on highway trips which considering its a full size truck is pretty decent. I still see people with small trucks having trouble getting 20mpg, freind of mine bought a brand new toyota tacoma last year and I'm beating his gas mileage still, his v6 to my v8. Though I killed my economy when I switched tires :(