i installed my new y-pipe today and when i drive it (only in gear, never neutral, park or idle) it makes a banging/ vibrating sound. i think it may be coming from the pipe just behind the cat hitting the crossover. is this possible? need help here fast plz.

 

you need to unbolt the crossmember and insert 3 or 4 big washers on each bolt (between the crossmember and the car subframe). this will "push the crossmember down" and give you enough space for the b-pipe not to bang. Some people just take the crossmember off completely....but I prefer to have it on with the spacers.

You can also try putting hose clamps around the rubber b-pipe hanger to "jack it up" a bit higher.

 

Nikita and I have taken both of ours off and have felt nor had any adverse effects from doing so.

.....and yes it is your crossmember that is in the way.

 

arright, well i messed with the hangar, guess ill put in some washers tomorrow. thanks guys

 

That's because you two drive like little girls (and only one of you actually IS a little girl)