Steven6095

Whine is constant higer pitched with more speed
louder on accel and deaccel but can easily be heard over the radio at a constant speed.

"From what I've read on both the V6 and the GT model it's hit or miss as to whether you'll get a rear end that will not make noise with a gear change. I haven't read of anyone with one the noise problem after a gear change getting it quiet again. "
Why why why why why? There HAS TO BE something with these rear ends.

Sherwood06GT

I had 4.10s installed last summer and from day one they whined. A couple of months ago it started getting much worse. I had the shop install a new set of Ford Racing 3.73 two days ago and they found that one of the bearings was broken. They said it was most likely due to the gears being to tightly crushed and possibly a defective bearing. The noise was constant. After the new installthere is no gear noise at all. Very quiet. All I can hear now is the SC!

Steven6095

A crushed bearing would have been obvious I assume to these guys

Haulupki

Seems like the carrier or the rear housing,may be machined out of spec. The carrier can be checked for run out or perpendicularity between centers on a lathe with dial indicator. The housing is a little tougher to check. and requires some special made fixtures . I think that changing the carrier is a real good place to start.......

Steven6095

Here is the thinking:
OEM gears and diff made no noise.

Two gets of gears, full bearing kits, numerous installs + these guys yesterday.
Noise has remained the same.

Gears have been changed and the noise is still there. Noise started with gears and diff install.
Diff is still the same.......

06hoss

I forgot I wasoutside ofthe GT section...duh!

Steven6095

Whole rear axle from a wrecked GT is also a card that may be played

Steven6095

Any more comments? Possible issues, etc?

drbobvs

Well I have the 3.73's and they have a high pitched whine starting from 50mph and gets higher in pitch from there. It only occurs on the drive side of the gear and stops once you take your foot off the gas.

I've had the gears changed twice, lined the car with dynamat, even used that Redline Heavy Shock-proof gear oil that Crazyal recommended and it's still very audible with the top up. Now I'm pondering the possibility that it's the center carrier bearing of the 2 piece drive shaft since when driving it's really hard to pinpoint the exact location of the noise. Although, at this point, I'm also pondering pouring gas on the whole freakin' car!

my77stang

yeah this is EXACTLY what im thinking, why arent there problems from the fast paced assembly line but when it comes time to install "better" gears everything goes to crap. I really dont get it.