Smell of diesel fumes located!

[monoblock]

Does your truck smell (more than it should) of diesel fuel fumes?
I found a concealed leakage point that is easy to test if you know where to look.

I had just removed the bed from the truck so that I could fit a dump mechanism. Poking around I twisted the huge screw ring on top of the fuel tank. This huge plastic ring was not even finger tight ! The rubber seal around the ring was wet with diesel and there were tell-tale diesel fume+muck stains on top of the tank. I managed to tighten it by hand at least 270 degrees.
With the truck bed in place I think you could still reach up there to test/tighten it. Be careful not to twist all the hoses/wires that enter the tank at this point. A simple strap wrench might help.
Another issue I had to correct was the "U" shaped rubber/plastic buffers (that prevent the steel straps around the tank from chaffing the plastic tank) had become dislodged/lost. I replaced them. With the bed in place you would not be able to see this.But it would be easy to feel along the top edge of the steel straps to locate any buffer strips.

While you are under there, feel along the top of the curve of the exhaust where it kicks up over the axle. Right along the top ,mine had a deep crease/kink that would cause a restriction. The muffler shop had done a clumsy job ? You couldn't see this w/o taking the bed off but it is easy to check by feeling along the top of the exhaust with your finger tips.
Hope this helps.

[oldestof11]

No fuel pump in the tank.

The exhaust thing is a 1st Gen stock exhaust thing.

[PToombs]

Jon, if it's loose it can seep around the seal. Not having a pump has nothing to do with it.

[oldestof11]

I just don't want this guy disappointed to find out that someone replaced the fuel pump in his tank that isn't there.

[cougar]

I know my fuel tank leak there. I'm just too fat to get in their and fix it. Guess I'll have to take the bed off.

[monoblock]

You may be able to slip a big strap wrench around the sealing ring and tighten it. Just be careful the whole assembly does not rotate and strain wires/hoses. I did this with the bed off so it was easy so your experience may vary!