In 2013, on my first leg of vacation I filled my spare fuel cans in Fairbanks like I always do while topping off fuel in Salcha and Tok on my way into Canada and of course stopping at Border City Lodge to top off there before crossing the border to save a few bucks, however to my surprise there were new owners that took over the place (nice folks) and they were in a unique business situation to where they could not sell any fuel thanks to the former owner running the place in the ground.....he felt bad for the many commuters stopping in requesting fuel that he referred them to Tok or Northway Junction.
There were two commuters that pulled in and asking me if I had any extra fuel to sell them while I was talking to the new owners as I told the one man (Alaskan) his best chance was to go back to Beaver Creek because he estimated he had about 50 miles left in his tank and knows he won't make it to Tok (a Toyota sedan) as I also told him Northway Junction at the native store is a crapshoot for fuel sometimes....I told the guy what spare fuel I have on me I might really need to make it to Whitehorse with, and of course he reminded me I can refuel my gas cans in Beaver Creek or Destruction Bay as they have gas there, but yet he decided to skip those 'expensive fuel' stops and make it back into Alaska for cheaper fuel without being prepared for the "what if".....and this guy is Alaskan, he should have known better with only 3 potential gas stations in between Haines Junction and Tok stretch.
If one was "actually stranded" on the side of the road, I would have rendered assistance and sold fuel in that situation.
Yes I am one to save a few bucks and stretch out my funds for the long haul like others however I was well prepared by carrying spare fuel like I always do travelling in the far north, you just never know if a road closure will happen due to a flood, landslide, or forest fire where you might need to turn around where one has already committed in a long distance stretch between fuel stations, or some refinery blows up as there is an immediate impact of a disruption in supply as the essential locations with the most demand gets replenished fuel upon first tabs.
In 1991 I seen Watson Lake run out of fuel as many commuters were waiting for fuel for a day and a half in which I went to the Watson Lake Airport and bought fuel with no problem and continued on my way (I can only run 100 octane AVGAS in my 70 Thunderbird in which I carried 32 gallons of spare fuel in 6 jerry cans.)
Since obtaining my camper in 1996, I only had to essentially tap into my spare fuel on two occasions (all between Whitehorse and Tok stretch in 11 total times) as I watch my altimeter gauge for thinner air readings and moisture days (water grains in the air) in which those two factors for my rig can potentially not make the stretch between Whitehorse and Tok without refueling.
I will generally dispense my spare fuel at Fort Nelson upon returning northbound towards home as Fort Nelson in general (out of all the major towns on the Alaska Hwy.) has the highest fuel price (or cheapest most expensive price one can get by with on the commute), as that 10 gallons of Fairbanks gas dispensed to top off my tanks in Fort Nelson saves me $14 to $20 depending on prices, as I just face a low risk of fuel disruption at Watson Lake without onhand spare fuel as I can easily make it there with fuel to spare in the tank.
Once I fill both tanks in Whitehorse on my return home to Alaska, I determine whether to carry spare fuel again (just 5 gallons) as my rig in most cases will make it from Whitehorse to Tok without refueling but air pressure and water grains or heavy rain will lower my fuel mileage more significantly between Whitehorse and Tok which is within the threshold for my rig running out of fuel in that stretch without refueling versus driving in a headwind which I calculate an additional 15% decrease in fuel mileage for those occasions anyway which will normally cover the spare fuel potentially needed.
A real close fourth occasion for dispensing spare fuel was closely imminent in the Northwest Territories as this was unchartered territory for me and sure was even more remote than I imagined than just being remote.
Wasn't sure if the Fort Liard store was going to sell me fuel because of the vibe that I felt they didn't want to sell me fuel, and I was asked 'how much fuel' by the clerk, as I told him no more than 60 litres just to top off my one tank, and he said ok.
Good thing I did get the fuel in Fort Liard because when I got to Fort Simpson, the one of two stations closes on Sunday and Monday, and the other one was out of fuel as they estimated delivery in three to four days as of course I arrived on a late Saturday afternoon as the other station closed early Saturday afternoon.
When I looked back on the trip between Fort Nelson and Fort Simpson and why there was no fuel in Fort Simpson and the vibe about Fort Liard, my feeling was they were dispensing more fuel than usual because of the Petitot River Pow Wow event they had near the NWT border (in which I was surrounded and told by 30 first nations at the acrow bridge that I had to go to their pow wow 80 kilometres up the road), and of course I complied to their demands and stayed three hours when I arrived there.
I was more likely under one gallon of fuel by the time I made it to Fort Providence (thinking I hope they have plenty of fuel there) or else I would have had to tap into my 10 gallons of fuel and reroute my trip to Enterprise or Hay River continuing eastbound just to get fuel, because there was no way I was going to make it northbound from Fort Providence to Yellowknife on my spare fuel reserve upon my last resort for fuel....if it were not for Fort Liard selling me fuel, there was no way I could have made it to reach Fort Providence on the fuel supply I had onhand, or burn three to four days or whatever time the fuel truck would arrive to replenish fuel in Fort Simpson before moving on.
Since Fort Providence had fuel, I could have only purchased 12 gallons of fuel at the minimum knowing I can make it to Yellowknife however because this was unfamiliar territory I decided to top both my fuel tanks in Fort Providence and didn't matter to me what the cost was for fuel, what mattered to me was not to potentially be stranded....I seen enough tankers and semis headed to Yellowknife so I figured even though this road was a lifeline of Yellowknife with a lot of commerce, I had piece of mind of adequate fuel supply going towards Yellowknife while knowing I can make it back to Fort Providence at the crossroads just in case the "what if" were to happen with a potential forest fire closure (and it was a dry summer in NWT in 2008 with fires around) or if there were a disruption in fuel supply in Yellowknife with my luck.....at the time Yellowknife fuel was 7c per litre cheaper than Fort Providence and yes I could have saved between $11 to $20 depending how and when I dispensed fuel in Yellowknife in the calculations, but that one $20 note in such a remote region was worth the piece of mind with adequate supply of fuel in practically no mans land.
As Joe mentioned, refueling when your tank is half full in the far north is wise and you shouldn't have a problem with running out of fuel on your commute, while although it is not as essential to carry spare fuel as others noted in the past reference to past posted related topics on fuel availability, I always made a habit of carrying spare fuel for reasons and experiences stated above.
Happy and safe travels to the far north.