Do they have to be on each side? Can I get away with using a little silicone on one side? Also if I need one is this a direct GM Item only?

 

I got mine from combantion motor sports but I would say your local parts store has them and yes they have to be on both sides you could try silcone but I would just get the gaskets.Dont want to clog the whole's up...

 

A washer is meant to be used on each side of the tube. That's the way I would do it and not try to substitute some sealant. Though I don't know for sure, my guess is that it is a GM only part (10108689).

 

Save yourself the trouble later down the road and don't try to cut corners with these, it's not fun having to go back and re-do it. Get the right stuff the 1st time.