Actually sounds more like a horn blowing when cruising at a steady speed on the highway. Have noticed it seems to be getting louder. Plan on taking it in to the dealer later today but am clueless about what the noise is. Seems I remember a tsb about gear whine and the fix is an additive to quiet it. Sound right to you guys?

 

This is all I can find for a TSB close to that:

Drivetrain - Rear Axle Hum/Whine

TSB 05-20-2
10/17/05
REAR AXLE NOISE
FORD:
2005-2006 Mustang

ISSUE
Some 2005-2006 Mustangs may exhibit an axle whine or hum during acceleration, deceleration and/or cruise.

ACTION
An axle repair kit has been developed which incorporates most parts required for a comprehensive axle repair. The kit should be used instead of installing a complete axle assembly to repair an axle whine/hum.

Replace Ring and Pinion with Axle Kit and Components
SERVICE PROCEDURE
NOTE REFER TO THE "DIFFERENTIAL RING AND PINION" IN-VEHICLE REPAIR PROCEDURE IN THE ONLINE WORKSHOP MANUAL SECTION 205-2A (7.5 INCH AXLE) OR SECTION 205-2B (8.8 INCH AXLE), FOR THE LATEST AXLE DIAGNOSIS AND REPAIR PROCEDURES.

THE AXLE SERVICE KITS INCLUDE THE FOLLOWING COMPONENTS:




^
4630 - Head Bearing


^
4628 - Head Bearing Cup


^
4676 - Pinion Seal


^
386989-S2 - Washer (Slinger)


^
4621 - Tail Bearing


^
4616 - Tail Bearing Cup


^
4222 - Differential Bearing Cups


^
4221 - Differential Bearings


^
4209 - Gear Set (includes pinion shims, pinion nut and crush spacer)


^
4209 - Instruction Sheet
NOTE REUSE OF RING GEAR BOLTS, CARRIER BEARING CAP BOLTS AND DIFFERENTIAL SLAVE PIN RETAINING BOLT REQUIRES CLEANING OF THREADS AND INSTALLATION OF TA-27 THREAD LOCK ADHESIVE ON THE RING GEAR BOLTS AND TA-25 THREADLOCK ADHESIVE ON DIFFERENTIAL SLAVE PIN BOLT.

NOTE THE KIT DOES NOT INCLUDE THE FOLLOWING ITEMS. SOME OR ALL OF THESE ITEMS WILL BE REQUIRED TO COMPLETE THE AXLE SERVICE, DEPENDING ON AXLE APPLICATION/STYLE.

ORDER AS NEEDED:




^
4067 - Differential Shims 0.241"


^
XY-75W140-QL - Synthetic Rear Axle Lubricant


^
XL-3 - Additive Friction Modifier (Limited Slip Axles Only)


^
ZC-21 - Metal Surface Cleaner


^
TA-29 - Ultra Silicone Sealant


^
TA-27 - Stud and Bearing Mount Retaining Compound and Sealant


^
TA-25 - Threadlock Adhesive


^
XG-14 - Gear Marking Compound

















Parts Block
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty CoverageOPERATION DESCRIPTION TIME

052002A 2005-2006 Mustang Install 5.5 Hrs.
The Parts Included In Kit,
Includes Time To Perform
Diagnosis: (Do not use
with 4205A, 4205A4)

DEALER CODING
CONDITION
BASIC PART NO. CODE
4209 42

OASIS CODES: 509000, 597997, 702000, 702200

 

Thanks Mike. It's at the dealer now getting new gears put in so I'm sure this is the TSB they're going by. Should have it back by wednesday. Sure hope they have a good tech that knows what he's doing lol.

 

I'm feelin' ya. I'm taking mine in for a gear install today. I really hope they get it right and it dosn't whine. It's got me nervous. [sm=signs003.gif]

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