Last night I had my first opportunity to crawl around under my truck. I noticed there is some type of cooler right in front of the gas tank. I followed the lines up into the engine compartment, but it was dark and beginning to rain, so I couldn't figure out what they were going to. What is that for?

A fuel cooler, it cools the fuel right before it goes back into the tank. its on the return side.

Thanks ratlover, seems like a vulnerable place to put it to me though even though it has a screen on it. Has anyone seen one of these ruptured by debris?

None thay I have heard of.

I seem to recall a discussion that the fuel cooler is there to insure that hot returning fuel does not melt the plastic fuel tank. If that's really the case, it's too bad Transfer Flow didn't know about it. They could easily have gotten another 10 gallons or so in their replacement tank by removing that cooler. They went to a lot of trouble to make their tank fit around that cooler.

I don't think it has anything to do with the plastic tank....

If the fuel isn't cooled, then asphaltines will form. Asphaltines are "tarballs" that can plug your fuel filter and your fuel injectors. There is a good discussion of this (and fuel stability) on chevron's website.

- jeff

The fuel is the coolant for your fuel injection system. The cooler keeps the fuel temp cooler which keeps your fuel injection system cooler.

You should probably replace that gas tank with a diesel tank ;)

What rockin said. I havent looked much but the few times I've had it hooked up to a scanner I saw fuel temps 115+ and that wasnt a real hot day or doing anything stupid.