I've got a 97 dodge ram and I'm currently at work. I went and put $60 in gas this morning and noticed my tank is leaking from the top somewhere, I can't see much. But has this happened to anyone else?

 

Plastic tank.... but, I think a steel ring that secures the fuel pump module to the tank. They like to rust out. Gonna have to go exploring, and see where the gas is coming from.

On mine, I had to replace the filler neck, as it rusted out..... really was only an issue when getting gas, but, given the prices..... its a lot like pouring gold on the ground.

 

I had a sending unit plastic retaining ring being loose, tightened it and no leaks after that.

 

I just got it home and looked at it, it's not leaking from the around the fuel pump. It's somewhere in the middle of the tank. I plan on taking the bed off later and seeing if I can find where it's coming from

 

Fire it up and see if it leaks while idling. I've had rocks get up on top of the tank and chaff through the line.

 

It's leaking from somewhere behind where the frame sits in the groove of the gas tank. You can't really see behind it but I believe it's cracked back there somehow. I plan on dropping it tomorrow and seeing what's going on. What's the best way to patch a small crack in the tank?

 

Plastic weld. If it's small enough, testors model cement may work. It actually melts the plastic back together.

 

The type of plastic Dodge auto parts are made of is cast into many of the pieces. To help a tech decide how to repair them, would be my guess as to why.
HDPE, high density polyethylene, is your fuel tank, difficult to glue. Solvent type adhesives will work on ABS, not polyethylene.
Mechanically weld the plastic, soldering iron temperature heat, or one of the exotic adhesives from somebody like Loctite, whatever is available to you that will stand up to fuel.