382WS6

My car runs great up until it hits 80mph. At that point I'm at 2500rpm. I get this horrible, loud droning noise coming from the center of the car. It's loud ebough that it rattles the change in my ashtray. I'm at a loss as to where it's coming from. Can't tell if it's driveline or exhaust. Anybody have any ideas or similar experiences?

MJK

iTrader: (3)

Just a few things to check man...

Could be as simple as maybe due for fluid changes (tranny/diff..)
Check for odd wear patterns on your tires...
Tranny mount...
Check for odd wear on your rotors,damaged calipers...(braking system)
Exhaust clearance issues..

Just some ideas man...I'm sure you have thought of most of them already...

contraststriker

iTrader: (14)

I'm really thinking driveline. Check your torque arm bolts as well as what MJK suggested.

382WS6

Brakes are good, tires are worn, but evenly, tranny mount is brand new. I did just put a new y-pipe with a magnaflow cat on it... could that be it? And if so, how the hell do I get rid of it? Other idea.... what about the rearend? Does that start to vibrate when it's about to blow?

staringback05

iTrader: (8)

id still check any and all mounts

ZoFastSS

iTrader: (5)

The only droning noise I ever had was a little at around 65, I figured it was because I had the cats removed.

Pewterpower

A new or different exhaust will definately bring out moans and rattles that you've never heard before. Especially at WOT.
One time, I had my 10 yr old son crawling around the interior of the car while I made it rattle. He was able to pinpoint the area it was coming from, and it turned out to be the tunnel brace.

ChocoTaco369

driveshaft? maybe you need new u joints.

Switchblade

Do you reinstall the stock tunnel brace after the Y-Pipe/Catback Install? If so, then check the clearance between the tunnel brace and the Y-Pipe. If the pipe is actually on the brace, then that's what could be causing your problem. That's what I've found out when I installed the SLP Y-Pipe - basically the stock tunnel brace would not fit properly with the new Y-Pipe in Place. Of course I've didn't reinstall it - ordered a aftermarket piece.

Assuming that this is indeed your problem, then you'll have two choices; 1) add spacers onto the stock tunnel brace to get seperation from the Y-Pipe or 2) get an aftermarket tunnel brace (ie BMR, etc) that basically has more clearance than the stock piece when installed.

Also you should double check your exhaust set-up to ensure that there are no interference issues with the chassis or driveshaft - I believe you did this during the install.

Best of Luck