Gasoline Calculations

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boz4rnr

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I did a search on the forums and didn't see anything - so if this is a repetitive question, please forgive me:

This may be a newbie question, but I wanted to verify my thought process on the "somewhat" important question of "How much gas do I need for X trip?"

Example: I know my rig gets 16mpg fairly nekkid (no gear) with a mix of freeway/city driving. Fully loaded that number looks more like 14.5mpg. For safety's sake, I'll assume that climbing over the river and through the woods will knock that down to roughly 10mpg. I have a 23 gallon tank, but it screams nasty things at me if I use anything past 20 gallons (for good reason, I'm sure). Soooo... that means I have roughly a 200 mile range MAX that I'm comfortable relying on. Are there any holes/flaws in that logic/math?

Now... I have a 3.5gallon gas can... which I'm counting on for 30 miles of additional range (again, I like having some buffer). So, if equipped this way - I have a max range of 230 miles offroad before I should plan on rolling downhill or taking a brisk walk for more gas.

Again - are there any holes/flaws in my logic/math? Also, what are the average ranges for people in this group? If the average range is more like 300... I'll invest in more gas cans. If the range is lower - I'll stick with what I have. Thanks in advance for any feedback/tips/guidance/patience/etc.
 
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oneleglance

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Your math is right for the average planning session...
And here are some extra thougths.
During the trip monitor your usage by gauge,
Add fuel from your can as soon as you are 1/2 tank unless you are in real rock crawling country where keeping it in your can might save you from a tank puncture.
If you travel with others make sure each person has at least 1 can of fuel, and if someone has a truck with extra bed space maybe they would carry an extra can for ya.
Lastly there is something called "the point of no return" that is where you need to either turn around or get off trail for fuel. When I am doing my route planning I try to figure out where my exit points are that would mean either turning around or pushing sideways or onwards towards fuel.
 

1derer

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I've found its difficult to be much further then 100 miles from any gas station in western US.

However if you are getting out there its good to leave a little room as its easy to carry more then you need but sure sucks when you don't have enough. Good to calculate from your lowest calculated MPG.
 
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Trail_pilot

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Reading things like this really makes me realize I need to address my fuel usage. I get roughly 8mpg and have roughly a 15 gallon tank. basically I don't get far. If I am going on a longer trip I usually carry an extra 5 gallons but I thoroughly research my routes to make sure there are places to stop and get fuel along the way. I have enough extra storage for another 15 gallons if I am heading way out, but most of the time I only have about a 155 miles to get to the edge of civilization and then I head another 21 miles into the woods to camp sites. I really had to plan my trip in the spring that was 420 miles from home to Pennsylvania which I had to make a lot of fuel stops for. I used google to help plan the route which let me look into fuel costs along the way but I also like a buffer and I tend to give myself a lager one than most do.
 

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When planning a trip for my 100 series, I try to figure in fuel stops every 150 miles. With a 24 gallon tank, 9mpg on the trail leaves me a safety net of about 60 miles. I have never carried extra fuel with me on the trail, but some of my planning for future trips has shown that a 150 mile fill up might not be possible has led me to looking at fuel options. The most cost effective and unobtrusive route seems to be a long range fuel tank bolted under the rig.
 
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M Rose

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I did a search on the forums and didn't see anything - so if this is a repetitive question, please forgive me:

This may be a newbie question, but I wanted to verify my thought process on the "somewhat" important question of "How much gas do I need for X trip?"

Example: I know my rig gets 16mpg fairly nekkid (no gear) with a mix of freeway/city driving. Fully loaded that number looks more like 14.5mpg. For safety's sake, I'll assume that climbing over the river and through the woods will knock that down to roughly 10mpg. I have a 23 gallon tank, but it screams nasty things at me if I use anything past 20 gallons (for good reason, I'm sure). Soooo... that means I have roughly a 200 mile range MAX that I'm comfortable relying on. Are there any holes/flaws in that logic/math?

Now... I have a 3.5gallon gas can... which I'm counting on for 30 miles of additional range (again, I like having some buffer). So, if equipped this way - I have a max range of 230 miles offroad before I should plan on rolling downhill or taking a brisk walk for more gas.

Again - are there any holes/flaws in my logic/math? Also, what are the average ranges for people in this group? If the average range is more like 300... I'll invest in more gas cans. If the range is lower - I'll stick with what I have. Thanks in advance for any feedback/tips/guidance/patience/etc.
When you add the extra gas, it’s time to get back to town to find Fuel. besides Mileage, consider how many days you are going to be out, and how many side adventures you might have. Which also leads back to heading to a fuel station when you have to use the can...
 

oneleglance

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I've found its difficult to be much further then 100 miles from any gas station in western US.

However if you are getting out there its good to leave a little room as its easy to carry more then you need but sure sucks when you don't have enough. Good to calculate from your lowest calculated MPG.
It isn't much that you are more than 100 miles away, it is just that I would prefer to stay AWAY longer.
The north rim of the Grand Canyon is a prime example, you can go 500 miles west to east and not see a person but it sucks if you have to burn travel time to come out and get gas then go back.

Same for areas of Utah.....However if there are cool small towns we will try to plan every 300miles/3-5 days to have a stop over with a hotel/shower/refuel/resupply.
 

Trail_pilot

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It isn't much that you are more than 100 miles away, it is just that I would prefer to stay AWAY longer.
The north rim of the Grand Canyon is a prime example, you can go 500 miles west to east and not see a person but it sucks if you have to burn travel time to come out and get gas then go back.

Same for areas of Utah.....However if there are cool small towns we will try to plan every 300miles/3-5 days to have a stop over with a hotel/shower/refuel/resupply.
Head to northern Ontario and you need to be careful planning your routes. ones you get past a certain point... pretty much the central to northern Ontario line, the gas stations are few and far between. I almost ran out of gas on my way to Killarney ( near Sudbury) from Parry Sound because I missed a fuel stop and didn't turn around. pretty much rolled into camp on fumes and had to double back to a reservation to fill up. where I normally go now takes a half tank to get in to camp and a half tank out, so if I do any exploring I need to bring extra fuel. This is also because my rig is thirsty... very thirsty.
 
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Itacal

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Reading things like this really makes me realize I need to address my fuel usage. I get roughly 8mpg and have roughly a 15 gallon tank. basically I don't get far. If I am going on a longer trip I usually carry an extra 5 gallons but I thoroughly research my routes to make sure there are places to stop and get fuel along the way. I have enough extra storage for another 15 gallons if I am heading way out, but most of the time I only have about a 155 miles to get to the edge of civilization and then I head another 21 miles into the woods to camp sites. I really had to plan my trip in the spring that was 420 miles from home to Pennsylvania which I had to make a lot of fuel stops for. I used google to help plan the route which let me look into fuel costs along the way but I also like a buffer and I tend to give myself a lager one than most do.
I've yet to do anything that takes me more than 25 or so miles from a gas station, but this year, I am planning some longer trips/stays in the woods. I've actually been looking at how many Rotopax I need and how big they should be.
 

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Florida by the Glades, some areas of canada, and some of our stormy great plains areas, it was really easy to accidentally take my fuel capacity for granted, and then barely make a station. And that's back country pavement and dirt roads. Not the more adventurous stuff ya'll do in the west.

Your range is 115 miles. That's the only math you got wrong. Plan to only use half of what your carrying.

If we want to do it right, only plan to use 1/3 your capacity. Leaving 1/3 for emergency, or unplanned problems. And 1/3 for the other truck riding with you.

The next rig I build, I want a 500 mile max range, at 45mph, gravel. (11-12mpg) Hopefully some canada, Alaska exploring.
 
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