Whine in 5th gear...

I have a manual GT and since 2500 miles (i have about 6000 now) there has been a very noticeable whine in the back of my car whenever i'm in 5th gear...its most noticeable when i'm floating the throttle. And there is no sound at all in any other gear...Is it the differential? Is anyone else experiencing this problem?
 
I have the same issues... jet whine at about 2K in 5th. Mainly on the upside not the downside of hitting the gas. When I let off... it goes away, the slightest touch of the pedal brings it back until i let off again. Gets rather annoying.
 
CaptainSaveAHoe said:
I did have it checked out, I went to the dealership, described it to them, and they told me they didn't hear anything unusual during their test drive. But i'm not a psycho, I've had numerous people comment about it...I guess i'll take it back again

I had a whine from the rear of my 04 Marauder under the same conditions as you described. I blew it off until I noticed the rear cover leaking oil. brought it to the dealer for the leak and asked them to check the rear and bearing if the oir was low, &, mentioned the whine. Dealer called me and said the rear end neaded a new gear, carrier, bearings, etc. Rearend rebuilt under warranty. The sound was very weak. Most people could not hear it.
 
my car has about 1200mi and I started hearing the same thing (jet sound, very subtle) not a concern at this point

I only noticed it after I lowered the car, (pro kit) could just be timing?

I replaced the orig. panhard bar with an adjustable alluminum one with rod ends at same time

could be (for me) the higher spring rates and solid mounting of bar made the allready present noise more pronounced

also, besides the rubber mounts on stock bar, it is filled with some sort of medium/beads likley for dampining reasons, anyone else who removed (heavy) stock bar notice this? (if so, post mfg. date)

there has been a TSB for rear end noise I think, the fix is a dampner installed on axle, maybe on later cars like mine they solved the problem by using a bead filled panard bar to isolate noise/vibes
 
Keep any documentation the dealer gave you about their diagnosis. The rear should not be as loud as yours seems to be. The fact that it happens under acceleration could mean the diff gears are not aligned, could also be a bad pinion or gear ring.

If it gets louder or really bothers you get them to drive yours and another back to back to show you that it is 'normal'. Then be a polite jerk about it and have them visually inspect the rear-end (i.e. remove the cover).