Good rubber gas filler seal

[slikside]

When the seal on my gas cap was no longer effective, the cap would wobble around on the filler neck, and leak when the tank was full.

I made a gasket out of bicycle tube rubber, and used that to "tighten up" the fit. I know, sounds cheesy. But it works like a champ...still, and you can't see anything different from the outside. I'd definitely do it again the same way.

EDIT: I just realized your talking about the filler neck to cab gasket...sorry.

I bought mine from GMCPAULS, and it's holding up well...going on 7 months now.