Yes, a different adhesive would do the trick. If one could find out what cement the factory used, or what materials the cap is made from. It doesn't seem to be PVC. The PVC cement let loose, even though I had run the parts through the dishwasher(so I know they were clean!)

But I can't try another fix, as the internals are now gone.

 

I think it might be ABS. However "Plumber's GOOP" will stick to most anything even CPVC (Paint bucket).

If you use PVC cement you have to remove the outer skin, that's what purple primer does. Then the plastic welds. So you wouldn't want that anyway.

 

I would guess the material to be a high-temp nylon with a glass filling. Maybe PA612? It's what's used in most ABS Sensors inside brake hubs...

 

Got my new filler cap from Summit today. You called it, it's been backordered for a while.

G/M PN 12594232 CAP,OIL FIL(W/SEAL)(VENTED)(ACDelco #FC225)

Interestingly, listed as correct for SS, but 2008 only. The only other SS choice is GM P/N 12583570, which is correct for 2008-2010, but is non-vented. My 2009 was vented, unless someone had replaced it with the incorrect part previously. Seems somewhat unlikely, not impossible.

But 2008, some got vented, some got non-vented? Mid-year change? Why? I don't know.

I'm interested to see what cap y'all have. On the bottom of the cap is a central nub, and a hole or gap on the side of the nub. This is the vent. Maybe non-vented has no nub?

 

I have a 2009 SS and the cap is non vented.