MAXedOUTfx

do i need to replace the gasket from the ypipe to the cat? is that the reason why i am getting less miles per gallon?

Max96

You can re-use the stock metal gasket as long as you didnt destroy it when you removed the original Y-pipe. I used both of the old ones (OEM metal gaskets) on the cat, and there is no leak whatsoever. Please tell me you used gaskets when you put it back together.

MAXedOUTfx

ah great...i don't think the installers put back any gaskets...ah ****s///could this be the problem????