[quote author=roaf85 link=topic=157439.msg3360640#msg3360640 date=1255025302]
[quote author=bbf2530 link=topic=157439.msg3360476#msg3360476 date=1255020217]
This reply deals solely with running the tank to empty.
However anyone may feel to the contrary, Ford specifically warns against running the tank to empty, or running out of fuel. Directly from the Owners Manual:
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
effect on powertrain components.
Actually it is not an old wives tail, since running the tank down to the bottom concentrates
the contaminants in the tank. That means that at any one moment, the fuel pump is lines are pulling in more contaminants than if the tank had more fuel in it.
In addition, many modern fuel pumps 9I am not 100% sure about our fuel pump) have two pickups, so running the tank low forces the fuel pump to use the lower of the two pickups. That equals more contaminants.
Also, many modern vehicles use the fuel to cool the submerged fuel pump. So you run the tank low, you can overheat the fuel pump.
Just a few reasons to avoid running the tank low, if possible.
Hope this information helps.
Question about contaminants. I am not a scientist, but I was wondering take this for example:
Turn some dirt in a glass and then pour some water into the same glass. Notice how the dirt mixes and then settles to the bottom.
Does this same thing happen lets say on the road if you are hitting bumps and turning etc. Doesn't the contaminants swirl around in the tank and intermix with the fuel? I am just wondering.
Less so when the tank is full, or fuller. There is less turbulence in a full tank, since there is more liquid and less air space. So any mixing contamination is more dispersed/less concentrated, if picked up.
In addition, a full (or fuller) tank also promotes less condensation in the tank, meaning less water in your fuel tank, which means less water in your fuel.
Just more (of many) reasons why it is always better to keep the tank on the full side.
This is common automotive information, although some may not know it.