This article supersedes TSB 07-22-08 to update the Part List.
Some 2005-2007 Mustang GT vehicles equipped with the 8.8 inch limited slip axle may exhibit a moan/groan noise when making tight low speed turns. This may be more noticeable when the axle is at full operating temperature. The noise may also be confused as originating from the brakes or steering system.
Follow the Service Procedure steps to correct the condition.
First, verify the concern.
Make sure the axle is at full operating temperature.
Perform several full lock turns at low speeds in both directions.
If the noise is verified to be in the rear axle, proceed to Step 2.
If the concern can not be verified or the noise is not coming from the rear axle assembly, do not continue with this TSB and follow normal diagnostics in the Workshop Manual (WSM).
For vehicles built before 10/22/2006, replace the limited slip clutch pack. Install the new limited slip clutch pack kit following the procedures in the Mustang WSM, Section 205-02B (Differential Carrier Removal and Differential Case/Ring Gear Disassembly).
Vehicles built after 10/22/2006 were built with the new limited slip clutch pack. For these vehicles, add 1 bottle of Motorcraft® Additive Friction Modifier to the axle. Perform several full lock turns at low speeds in both directions to force the lubricant into the limited slip clutch pack.
DO NOT INSTALL NEW LIMITED SLIP CLUTCH PACKS IN VEHICLES BUILT AFTER 10/22/2006.
Motorcraft® Additive Friction Modifier
Eligible Under Provisions Of New Vehicle Limited Warranty Coverage IMPORTANT: Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.
2005-2007 Mustang Built After 10/22/2006: Add Friction Modifier, Includes Time For Road Test (Do Not Use With 4205A, 4205A4, 4205A12, 4205A13, 4234A)
2005-2007 Mustang Built Before 10/22/2006: Install The Limited Slip Clutch Pack, Includes Time For Road Test (Do Not Use With 4205A, 4205A4, 4205A12, 4205A13, 4234A)