I have a 1968 Kaiser jeep M109 van body truck. The engine is a non turbo multi fuel. The fuel economy has been bad from the beginning. I get about 5-6 MPG in normal driving on paved roads at speeds around 55-60 MPH. Is this pretty much normal for this truck? I do not have any upgrades like lockout hubs, which would definitely help.
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M109 fuel economy
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muddog
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My 109 gets 12mpg on the interstate, don't know about others except for a friend of mine he said his got decent mpg.
Harold
Harold
Westech
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have you changed all the filters? have the Tires inflated to the correct pressure? adjust the brakes to TM specifications?
A
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Mine gets 12-13 highway running on 50/50 wvo/diesel
City I never tried since I never drive it into the city.
City I never tried since I never drive it into the city.
mdmorgan
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You running stock tires? If so try slowing down a little, keep it between 45-50 and see how much it improves.
wreckerman893
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The vehicle has the aerodynamics of a concrete block......if you are running it wide open it will suck fuel.....mine did well when I kept it around 2300 RPM but sucked the bottom out of the tank if I ran it up against the governor.
Putting 1100x20 tires will help somewhat but you still have to keep your foot out of the firewall.
Putting 1100x20 tires will help somewhat but you still have to keep your foot out of the firewall.
wsucougarx
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I get around 9-10 MPG in mine
91W350
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Did you really type in 55-60? Mine never sees 50...
You are screaming down the road!
You are screaming down the road!
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I can't do 60 either, 55 I can manage flat ouy with a tail wind, but milage sucks then.
digitaldust
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Guys I dont know what your M109's are but Mines sees 70 - 90 All the time no BS however Its intermittent as I get passed by all the cars and suvs on the highway. My M109a3 goes 45 maybe 50 its really slow as all M109s I do get 16 in the city and 12 - 10 Highway.
I have a turbo whistler
I have a turbo whistler
wsucougarx
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Gunfreak25
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12, 14, 16 mpg? I have not seen numbers this high even with the M35 cargo variant? Huh?
steelandcanvas
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shenkmen
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70 - 90 mph?
gimpyrobb
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I have a non-turbo 109 and I get 8ish. I would try slowing down too.
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Best I've ever gotten was 11.5 in a 12,000# M275A2 travelling at 51 mph with lockouts on the front and one rear axle removed. This was a well tuned truck too. Anything better that that is really suspect to me, but there is not accurate way to get the tank filled to the exact same level every time.
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I get about 12mpg in the M109 concistantly. I usually drive 55mph max, which with the 11r20 goodyear G177's puts the RPM at 2200-2300. If I run up to close to 2600, it really sucks the fuel down. I get more like 6 or 7 MPG if I sustain 60mph for a long period.
And I burn almost anything in any mixture...
And I burn almost anything in any mixture...
peecook
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i have 395s and the fuel turned up. gps says 67mph and highway mpg is 14
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with my M35A2 with the cargo cover on (somewhat, but not quite a M109A3), i get 9mpg.... i havent driven my M109A3 far enough to check the milage yet.
saddamsnightmare
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June 26th, 2011.
I'm not challenging the OP here, but as for Digitaldust, if he's hitting 70+ in a stock M109 shop truck, several things are out of whack... 1. The Speedometer; 2. The GPS; 3. He's dropped it off a tall cliff.... There is no way a stock multifuel will hit those kinds of speeds with normal gearing and still have an engine left in the truck. My M35A2 with cargo cover will go 11-12 mpg if not pushed above 45-50, and with the 11:00X20 NDCC's on her she will red line at 60 MPH and the is just shy of blowing the engine out of her. What I will say to the OP is that if you are doing above 45-50 consistently, you probably are shortening the time to rebuild or replacement for your engine, as the long stroke diesels used in the deuce were not speed engines but rather torque engines...
If the duece is run below or above 80% normal output for very long, maintenence issues will be the result. These were designed as off road trucks, hence the tactical designation, and they are really intended for slow speed work in conditions a stock highway truck could not survive in. That is why there is no interaxle differential on the rear end and why the Army used a walking beam suspension system, not sophisticated, but reliable under the circustances. My truck's hour and speedometer togather indicated an average uise speed of about 22 MPH for the whole of the time she was used by the Army and her two prior civillian owners, and I have only upped it slightly as 98% of her time with me was spent in the mid 20 mph range... Even though she was used on several road trips of great length (for a stock deuce), it still worked out to the original speed range being the normal for her.
Next time you are doing 90 in gear, get a state trooper to radar gun you.... I'd like to see the report visually confirming that speed with the truck in gear.
Plus, fuel economy in a deuce, NOW there's an oxymoron!
I'm not challenging the OP here, but as for Digitaldust, if he's hitting 70+ in a stock M109 shop truck, several things are out of whack... 1. The Speedometer; 2. The GPS; 3. He's dropped it off a tall cliff.... There is no way a stock multifuel will hit those kinds of speeds with normal gearing and still have an engine left in the truck. My M35A2 with cargo cover will go 11-12 mpg if not pushed above 45-50, and with the 11:00X20 NDCC's on her she will red line at 60 MPH and the is just shy of blowing the engine out of her. What I will say to the OP is that if you are doing above 45-50 consistently, you probably are shortening the time to rebuild or replacement for your engine, as the long stroke diesels used in the deuce were not speed engines but rather torque engines...
If the duece is run below or above 80% normal output for very long, maintenence issues will be the result. These were designed as off road trucks, hence the tactical designation, and they are really intended for slow speed work in conditions a stock highway truck could not survive in. That is why there is no interaxle differential on the rear end and why the Army used a walking beam suspension system, not sophisticated, but reliable under the circustances. My truck's hour and speedometer togather indicated an average uise speed of about 22 MPH for the whole of the time she was used by the Army and her two prior civillian owners, and I have only upped it slightly as 98% of her time with me was spent in the mid 20 mph range... Even though she was used on several road trips of great length (for a stock deuce), it still worked out to the original speed range being the normal for her.
Next time you are doing 90 in gear, get a state trooper to radar gun you.... I'd like to see the report visually confirming that speed with the truck in gear.
Plus, fuel economy in a deuce, NOW there's an oxymoron!
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