took the car in for her first oil change. good thing i went in there with thr lube guy, there is a big oil leak from my rear.
im at the shop right now hopefully that gets fixed today.

 

they are gonna keep it overnight but i hope i can get it back on Saturday, need it to go somewhere on Sunday, hotels already paid for. : (

 

you're not the first '13 i've seen this happen to..they must have gotten a bad batch of pinion seals.

 

yeah, 8.8s are kind of notorious for this but usually it doesn't show up right out of the gate. It's a pretty quick repair if you know what you're doing though, no major disassembly required.

 

The dealership put a new seal on there, topped up the fluid, cleaned up the area. they did it fairly quickly and i was impressed.

I looked under after the dealership serviced it, they cleaned everything up it was dry, but after going through one tank of gas, i checked again, it's pissing itself badly again, and it looks like there is even more oil covering the bottom half of the diff housing than before....

Any thoughts guys? perhaps its not only the seal, a bad yoke, flange, etc? it's giving me a headache now especially with a brand new car with such low mileage and they failed to fix it once. hope im not headed down the road where its like some annoying problem that wouldnt go away for multiple tries.

 

Took the car in again today. good dealership first of all, they put the car up on the lift right away and had the mechanics looked at it.

They have no clue why it's leaking oil like that even with a brand new seal. the mechanic suspect that the refill port is designed too high and they just put too much oil in there. The Vent is also venting oil.

The mechanic checked for TSB, found nothing. They are contacting Ford for support....

the oil leak does not drip on the floor, as it only happens while the car is moving, so I imagine it drops a bit of oil here and there, but never where I parked. So maybe you guys should keep an eye for any oil marks on your diff housing too.

 

I believe that the refill port is not designed to be the full point of these 8.8s.

I've seen a tech manual or schematic somewhere that call for it to be a certain measurement below that. I can't remember the amount but I think it's 1/2" or so below the refill hole.

Don't quote me.

 

Chances are, when the axle was assembled, the oil fill was a preset system with a flow meter that dispensed an amount between a min and max designated by the design engineer. The pinion seal may be leaking because the third member (pumpkin) may have an abnormally large pinion seal recess, where oil could potentially leak around.

Sounds like you'll probably need a new axle.

 

There is a tsb for a new bladder style axle vent ... mine was leaking from the breather bad enough that it looked like it was leaking at the diff too. I had a bent axle flange too so the dealer had to pull the cover and change the fluid and re seal, no leaks since with the new breather.

 

If that is the case, Ford is gonna have a bunch axles with this problem.

 

After reading this thread, I checked mine and sure enough I can see some oil residue just like yours. It's not bad enough that it has left any stains on the garage floor. I will get down under there later today and see if I can figure it out where it might be coming from. Hoping it's just excess fluid from the factory that blew out...maybe?

 

It's almost certainly from the breather. As I stated earlier there is a tsb for a bladder style breather if it's leaking. Higher temps can cause the fluid to puke out a bit. The bladder gives more room for fluid expansion ...

 

That certainly helps ease my mind. Hope it's nothing serious. Thanks for the heads up!

 

Did a little bit of investigating and apparently this is a pretty common "issue" if you can even call it that.

http://www.mustangevolution.com/forum/f358/t298320/

 

the breather letting out a bit oil, but most of the oil on my car is leaking from the rear pinion seal now. dealership is still working on it.

a bit of oil is getting thrown onto the exhaust from the rotating yoke.

 

I know I am kinda late here but is there any new insight regarding the reasons (including damage risk and the cure) for the differential pinion seal leaking?

The reason why I inquire is that I have discovered an oil stain around the pinion of my 2011 GT (see attached picture). My car has run only about 30k kilometers and I have not altered anything except the panhard bar and support brace (Whiteline adjustable) cause I have changed to staggered wheels which is why the axle had to be centered.

When I sent the picture to my Mustang specialist (we don't have so many here in Switzerland), he wrote me back that it doesn't look that alarming and will be taken care of with the next annual service.

Can I be at ease?

Karl