over the past week or so i've noticed my car having an odd vibration when it comes down past about 2300rpm or so when driving normal and i just assumed it was my downpipe coming loose or being broken so i ignored it and just kept driving. well last night i swapped the stock downpipe onto the car and the vibration went away BUT my 3" downpipe was no where near being loose and I cant see as to where it would be broken... Is that just a fact of life with a 3" downpipe and stock catback or what? btw the car is completely stock now...

 

Could be but I always thought it was from my LW flywheel. I notice it in every gear for a sec or two under engine breaking, regardless of rpm.

 

Yes, I have a full 3" exhaust and mine does the Same thing.

 

mines bone stock, i guess its just a weird harmonic... i might throw some heat wrap on the downpipe when i put it back on to see if it helps dampen any sound...

 

Check your hangers . I had one replaced under warranty for a vibration on decel around 2500 rpm. It also droned at highway speeds around the same rpm on 5th. Had stock exhaust and 6 k miles only.