Rear axle moan fix.

[YardSpecial]

Good info Metro, nobody ever find the root cause. Just looking to lay blame.

I also think the factory LS is a great unit.

 

[bigcat]

Since no one here on Stangnet or The Mustang Source bothers to ask the dealership to HOLD the old parts and give them to the customer, no one has been able to answer my question: Does the factory use the carbon fiber clutches or are they using the standard clutches on the S-197 GT rear end?

the problem with this is that the dealer is required to keep the parts for a certain amount of time, just in case ford decides to review the claim later. the last dealer i worked at had several boxes of parts in the back. they were required to keep them for up to a year, then they can discard.

 

[Pro Mod]

I am not sure what the dealerships are doing, or what clutch packs they are required to use.

Since no one here on Stangnet or The Mustang Source bothers to ask the dealership to HOLD the old parts and give them to the customer, no one has been able to answer my question: Does the factory use the carbon fiber clutches or are they using the standard clutches on the S-197 GT rear end?

M-4700-C carbon fiber clutch kit: http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=6942

The standard clutches are used in 86-02 Mustang GTs and Cobras, while the 03-04 Cobra and the 07 GT500 are using the carbon fiber clutches. RUMOR has it the 05-up S197 GTs are using the same carbon fiber clutches, which might explain the unusual behavior (excessive groaning) since they are supposed to offer significantly MORE torque biasing than before due to the difference in friction materials. If the 03-04 Cobras never had this problem, then we must look elsewhere on the S197 GT.

NOW you're on the same page as me

I've never questioned the quality of the previous 8.8's... read my posts, I've clearly stated that they have been badass.
However with the S197's, Ford has changed something in the differential, and it is believed to be the clutches. I didn't request the dealer to hold my parts either, that never crossed my mind unfortunately. It seems with the TSB, they installed the same clutches that went bad. I do not have axle WHINE, I never mentioned that. Whine is not my problem at all. I have the low speed MOAN that is in connection with the clutches. I know MANY people who have had the TSB fix, and the moan came back. I know MANY people who added friction modifier and it was also only a temporary fix. Granted I also know a few people in which either one of those 2 methods did indeed completely cure their problem... but I know of too many people with the problems reoccuring, and it should be addressed by Ford.

I love the 8.8, but Ford needs to go back to the old clutches in these differentials. That is laying blame AND fixing the root cause.

 

[metroplex]

Have the 03-04 Cobra owners or 07 GT500 owners complained of the same low speed groaning during turns? It may not be an actual bona fide problem, just a side-effect of the different clutch materials. The carbon fiber clutches were intended for high torque applications (03-04 Cobra and 07 GT500 models aren't torque shy! :SNSign: ) so the "grippier" friction materials may be necessary for the required torque biasing.

Ford Racing never bothered to update their 2005-2006 catalogs to show the part # for the carbon fiber clutches, otherwise I would have bought them for my 00 Crown Vic to try out when I rebuilt a take-off/used Mustang GT T-lok unit

If the dealerships still keep your old parts, would it be possible for them to retrieve your old clutches just to confirm what type of clutches were used at the factory?

 

[bigcat]

If the dealerships still keep your old parts, would it be possible for them to retrieve your old clutches just to confirm what type of clutches were used at the factory?

only if they properly marked the parts before they stored them. then they also have to remember where they put them.

 

[Pro Mod]

Have the 03-04 Cobra owners or 07 GT500 owners complained of the same low speed groaning during turns? It may not be an actual bona fide problem, just a side-effect of the different clutch materials. The carbon fiber clutches were intended for high torque applications (03-04 Cobra and 07 GT500 models aren't torque shy! :SNSign: ) so the "grippier" friction materials may be necessary for the required torque biasing.

I believe it's just simply the new clutch material. I don't browse the Terminator/GT500 forums much, but of all the Terminator guys that I know I've not heard ANY of them complain about any axle moan.

 

[highvolts]

This is all good information, but what about a whine/moan from a 07gt with under 1000 miles when i'm cruizing at 65-80 MPH on the highway? Normal?

Metroplex, you talk about the straight line whine.. whats that about?

Thanks Guys!

-Jason