I've got a 2003 Hemi 1500 quad cab. My brothers had a chip in it but pulled it to trade for something for his bike. He's a ****. Other than that I have Flowmaster exhaust, K&N intake and everything else stock. I just flushed my transmission and used the 3M fuel system cleaner kit on it. Now for the question...

I get a bit over 300 miles to a tank. Strange thing is, I get over 200 miles to the first half of the tank and after that it seems to be a very rapid decline. My brother said he noticed this too but it didn't matter to him. If I'm going to get way better gas mileage on the first half of the tank, hell, I'll just fill the damn thing up at half a tank. However, it just seems strange to me. Does anyone else notice this or am I just crazy?

 

Just about all vehicles are like that the top half of the tank is bigger than the bottom half. Just like when you fill it it takes a long time for the needle to come off full then drops pretty quick the rest of the way. it usally takes from empty like 18-20 bucks to get half tank then another 35-40 bucks to fill it. every truck and car I have had is the same way.

 

its not that you are getting different mileage from the bottom half of the tank, its that the gauges are not very accurate when you start to get down near a half tank. its like this on almost every vehicle i have driven

 

+1 gauges suck on every fuel tank imaginable... gauges fail your eyes dont... but it is kinda hard to look into your gas tank...

 

Do you guys...you know...work? LOL! Ok...I had thought that, but was just wondering. My Cavalier ran about the same all the way though the tank, though I never let it (or the truck) dip below a quarter of a tank. My first truck was a 1975 Chevy Silverado that didn't have a working gauge in the damn truck and I just added aftermarket gauges but never a fuel. Nor a speedometer...who needs those?

 

Your truck tank fuel sending unit shows a full level at about 80-85% capacity. You should never fill your gas tank to the point where gas is coming out the filler neck. Gasoline does expand and contract in hot/cold and that's why the tank reads full at about that point. You and most people fill it up until the nozzle stops on it's own and then probably another 1/2gallon to "round" off the $$$ amount. Your getting an extra 2 gallons or so on top of the actual "full" level. Then when you compare your mileage from 1/2 tank down, well you obviously don't run your truck out of gas, so that leaves another 2 gallons at the bottom. That results in about a 4gallon mileage difference from top half to bottom half.

Hope that helps.

 

Oh no sir. Not me though perhaps others. First of all I don't want gas spills on my paint. Secondly, that's a pain in the *** and doesn't seem to be good so I don't ever click it extra once the nozzle stops. But the rest does make sense. I've run it pure to nearly empty once or twice, I simply don't like to because it's not good for the trucks fuel system.