saddamsnightmare
Well-known member
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- Abilene, Texas
October 2nd, 2012.
Gents:
I know that I am risking pouring fuel on the OP's fire, but let's stand back and consider a moment here the issue of fuel mileage with a M1009. It is, essentially, a 1975-1985 full size Chevy Blazer with some beefing up here and there, TWO (2) alternators, and a diesel that was probably a fair design then, but NO computer controls on the injection pump, probably only a governor. None of these trucks were aerodyanamic, as it has been said,a brick with a chunk cut out for the windshield. They are heavy, much heavier then their younger descendents, and they are geared for the reasonable speeds that the Army anticipated for convoys back then (40-45 MPH).
Any time you push a truck like this, the high clearance, cluttered underbody, square (rectangular, really) front end and the general effect of wear, tear and age on the vehicle and it's drive train, is going to impact mileage. Even the presence of a clean air cleaner element versus a dirty one can have an impact on economy. If you could do with less speed, there would be a possiblity for a more modern smaller diesel, and you'd do pretty well. Most Unimogs in this period, with a smaller gas or diesel engine then the Blazer has, will do better mileage on the average if you don't drag race, put your foot into it, or push the vehicle.
My Unimog with an 80 HP engine doing 50 MPH for ten hours a day getting here from Texas, did about 18 MPH with no headwinds and small hills, and that is with 7.65 to 1 final gearing. At the time, it had a Zyclone pre-cleaner on the air intake to free the truck from Texas dust in the oil bath cleaner. I took that unit off yesterday for maintenance, and I do believe that the truck is accellerating a little better, as there seems to be less impedence of the air flow. I suspect she will do better until I have to put the Zyclone on again to handle ice and snow conditions up here this winter.
So, if your truck is doing 13 to 18 MPG diesel, you're doing pretty good. Tires can affect it also, size, weight and hardness of rubber. Michelins roll better, but basically the rubber is so hard, they suck for traction on pavement. There will be variations from truk to truck based on maintenance and even the drivers that drive it now and back then, as they all have an impact on the trucks condition and behavior. This is just from my experience and an auto engineer will likely tell you something different. Good luck with your truck...
Gents:
I know that I am risking pouring fuel on the OP's fire, but let's stand back and consider a moment here the issue of fuel mileage with a M1009. It is, essentially, a 1975-1985 full size Chevy Blazer with some beefing up here and there, TWO (2) alternators, and a diesel that was probably a fair design then, but NO computer controls on the injection pump, probably only a governor. None of these trucks were aerodyanamic, as it has been said,a brick with a chunk cut out for the windshield. They are heavy, much heavier then their younger descendents, and they are geared for the reasonable speeds that the Army anticipated for convoys back then (40-45 MPH).
Any time you push a truck like this, the high clearance, cluttered underbody, square (rectangular, really) front end and the general effect of wear, tear and age on the vehicle and it's drive train, is going to impact mileage. Even the presence of a clean air cleaner element versus a dirty one can have an impact on economy. If you could do with less speed, there would be a possiblity for a more modern smaller diesel, and you'd do pretty well. Most Unimogs in this period, with a smaller gas or diesel engine then the Blazer has, will do better mileage on the average if you don't drag race, put your foot into it, or push the vehicle.
My Unimog with an 80 HP engine doing 50 MPH for ten hours a day getting here from Texas, did about 18 MPH with no headwinds and small hills, and that is with 7.65 to 1 final gearing. At the time, it had a Zyclone pre-cleaner on the air intake to free the truck from Texas dust in the oil bath cleaner. I took that unit off yesterday for maintenance, and I do believe that the truck is accellerating a little better, as there seems to be less impedence of the air flow. I suspect she will do better until I have to put the Zyclone on again to handle ice and snow conditions up here this winter.
So, if your truck is doing 13 to 18 MPG diesel, you're doing pretty good. Tires can affect it also, size, weight and hardness of rubber. Michelins roll better, but basically the rubber is so hard, they suck for traction on pavement. There will be variations from truk to truck based on maintenance and even the drivers that drive it now and back then, as they all have an impact on the trucks condition and behavior. This is just from my experience and an auto engineer will likely tell you something different. Good luck with your truck...
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