All Trucks, Campers, Trailers, RV's and Motor Homes - ’98 Nissan Frontier: So what is the fuel tank’s usable capacity?

I seem to be running out of gas much earlier than the 15.9 gallon fuel tank capacity shown in the specs…

Yesterday, the gas gauge on my 98’ 4WD Nissan frontier got on E, but a little bit below where I normally let it drop. I finished my trip and parked without any indication of fuel starvation.

However, the next day the truck would not start after several attempts.

So I got 2 gallons of gas (from the lawnmower reserve) and poured it into the truck’s tank. After 4-5 attempts at cranking the engine (5 seconds each crank) the engine started, very very reluctantly for the first 20 seconds and then started idling normally. I went to the nearest gas station (1 mile) and ended up adding another 12.1 gallons to fill up.

So, the 2 gallons I poured + the 12.1 gallons I added at the gas station make for a usable tank capacity of just 14.1 gallons (after that seems like I have to worry that the truck will not start or even stall on the road ? !). But I read in the specs that gas tank capacity is supposed to be 15.9 gallons ??!

Could it be that as much as 1.8 gallons of gas at the bottom of my tank are not usable?

Is there perhaps something else wrong, perhaps some weakness in my fuel pumping system that caused this problem?

Any advice appreciated.

It's possible and also not a good idea to let it run that low anyway because of the effect on the fuel pump. Keep in mind 1.8 gallons of a liquid is probably just a couple of inches (if that) when spread out over the surface area of the bottom of the tank.

My wrecker has 8 gallons unuseable in a 38 gallon tank.