[5LHO]

in only 7000 miles (32k to 40k) on this you probably haven't worn anything beyond saving...if you added the fricmod you could try it and then cancel your appointment if it solves it....honestly, I'm so sure this'll solve your problem; I just won't shut up about it.

Then you can find another dealer, hoefully without non-thinking parrots in the service dept.

[SixtyHertzHum]

Originally Posted by stevegt2012

I had to have the 3.73 ring and pinion replaced in my Brembo GT due to a whine. There is definitely a line item on the work order for friction modifier. So if they didn't put it in yours due to bad information or communication..... you see my point.

Thanks for chiming in, Steve. As a fellow Brembo owner, any chance you can comment on the clutch material first hand? Rumor was that to get carbon fiber from the factory on a GT in 2011 you needed to order a Brembo with 3.73 gears. I have yet to find the official documentation from Ford stating this though.

[FordCustSrvc]

Originally Posted by SixtyHertzHum

Right now I've reached out to Deysha and am hoping that my trip to the dealer later this week will prove more fruitful than the last

Thank you for the PM, SixtyHertzHum! I'll get back to you as soon as possible.

Deysha

[SixtyHertzHum]

I picked it up tonight. All they did so far was verify the fluid level in the differential, which of course was fine. They are apparently still on the phone with Ford concerning this, and fully expect to talk to them more on Monday. Thanks again Deysha (and Frank, regional customer service) for your assistance.

While at the dealership I spoke with the gentleman that helped me with the pinion seal replacement at 32k. I had him print out the work order, including all the materials used. Ends up that they didn't pull the cover and inspect the differential like I originally thought, so all they did was top off the oil with Ford "XY75W140QL". Since they didn't replace all of the oil, they didn't add any friction modifier, which he said was typical. Is it just me, or does this not make any sense? You make a solution of oil and FM, drain some out, add only oil - will the ratio of oil to FM be the same? I don't think so!

I am driving a lot next week for work and will be unable to get it back to the shop, so depending on how the phone calls go I decided to plan ahead and dropped the $6.62 on a bottle of XL3 which they had in stock. The oil they used and the XL3 check out according to the following lubrication specification document from Motorcraft.

https://www.fcsdchemicalsandlubrican...f/axlelube.pdf

Thanks again for the help everyone. Plans for now are to see what the dealer says Monday, but I'm betting that Monday night I'll be under my car in the garage (if not tomorrow).

[5LHO]

You can replace a pinion seal without pulling the cover if you're careful with your measurements of exposed pinion threads and pinion nut position. Filling with oil only could easily dilute the FM content to the point it makes noise, one the extant FM works its way out of the plates.

stupid *******, this thread boggles my mind. This is Ford and it's representatives at a dealer.

Thank you for acting on this by adding FM and potentially saving your trac-loc an ugly death. Based on what I've heard here so far, I wouldn't trust this dealer to wash the car much less perform any kind of maintenance or warranty work.

[SixtyHertzHum]

The dealer has been helpful to the extent they can be, and I will continue to be a customer of theirs. I do not expect them to do things that Ford doesn't want them to do, and am actually happy they're following Ford's direction on this and the pinion seal repair. Ford nor I want a dealer that ignores their repair procedures involving warranty work. The Ford customer service representatives have also been helpful. I see no reason to be upset with either party.

What I am upset with is the system that tells the dealership that they don't need to keep the ratio of friction modifier to differential oil approximately equal. For the trouble, I would have PAID for a complete drain and re-fill if it meant a spot-on ratio of those two fluids and a behaving differential (assuming, for now, that this is the root problem here). I am further upset by the fact that I have been repeatedly told, from Ford via the dealer, that this is "normal" (AGAIN today!) - when nobody from that group has seen or heard the problem 1st hand.

Thanks again for the help guys. I'll update here as things progress.

[5LHO]

It's just that Ford has been running 8.8s under Mustangs since 1985 and in millions of trucks and SUVs as well. T-loks like this one have been in these 3rd members (and in the 7.5s that preceded them) back to the late '70s. What the T-lok in these rear ends needs to work is about the most well-trodden ground possible.

[FordCustSrvc]

Originally Posted by SixtyHertzHum

I picked it up tonight. All they did so far was verify the fluid level in the differential, which of course was fine. They are apparently still on the phone with Ford concerning this, and fully expect to talk to them more on Monday. Thanks again Deysha (and Frank, regional customer service) for your assistance....

Thank you for the kudos and updates, SixtyHertzHum.

Deysha