Sorry if this topic exists elsewhere, but I did a search and didn't find anything. Possible that the rear u-joint seized, but I'm really not sure what happened.

2012 GT, manual, 3.55 axle, 1500 miles, no mods, no abuse (the engine hasn't even seen anything north of 6000 RPM yet - it is new and has been babied).

Today just after entering the interstate and reaching 60 MPH there was a loud squealing (and other undescribable noises) coming from underneath the car. Also the car began to lug as if something was dragging it down. It limped off the highway and has been towed to the dealer (they can't look at it for three days ). Observed leaking diff fluid from the input and smell of burning fluid in and out of the cabin and trunk.

Any thoughts from the forum? (Deysha has been PM'd too, just to see if she can help things along.) Needless to say, I'm not happy about this happening on a new car, but would appreciate any thoughts. Will update when the dealer looks at it.

 

Welcome!

That sounds pretty crazy. I Hope it turns out well. please keep us up to date.

 

Sounds like a gear in the rear end might have failed. Something similar happened to a truck I used to have. I had no warning, just made some weird grinding noises and then a pop. When the shop opened it up the o-ring practically exploded. I'm sure the warranty will cover it, if not it's perfect timing to install a 3.73 lol. Good luck and welcome to TMS!

 

Thanks for the welcomes.

Been lurking here for the past few months but wanted to reach out and see if anyone had any ideas while I wait for the dealer to get around to looking at it. (They put me in a Mazda 6 loaner of all things, so punishment upon punishment.)

Whatever happened occurred very suddenly and without warning. Something definitely got bound up in the rear end. The car was drivable but just barely. At least enough to get me off of the interstate and somewhere safer. There was a small puddle of diff fluid on the ground, dripping from the input, but not a lot (a few tablespoon's worth) and it stopped dripping after about 10 minutes while I was waiting for the tow. I don't know if there is any fluid left in the diff, or if there was enough in there to begin with, or if I lost a lot of it out on the highway. I suspect the u-joint seized and messed up the input seal, but that's just a wild guess on my part.

Took delivery of the car in early November with about 50 miles on the clock. My wife and I both love the car but are not happy with Ford quality right now. When bad things happen to a new car at 60 MPH on a busy interstate, I get concerned. Hopefully the damage is isolated so I don't have latent failures down the road. That is my second biggest concern, after the failure itself.

In the meantime I'm taking advantage of all that Ford has to offer - Roadside Assistance, free loaner, and warranty coverage. Hopefully not another dime out of my pocket, or I'm going to get rid of the car. The whole point of getting a new car as opposed to used was to have something that would be trouble-free for at least a few years. The tow driver told me he just towed a new Camaro with a blown tranny, and that owner was not a happy camper. I don't know whether or not that made me feel any better.

 

Welcome to the forum, MLM! Thank you for reaching out to me. I received your PM and will get back to you as soon as possible.

Deysha

 

UPDATE: Tech found pinion bearing failure. Said it looked rusted out. At 1,500 miles? Damage appears to be limited, though. Parts are on order.

 

After nine days at the dealership, finally got the Mustang back today! Suffering withdrawals. Dealer replaced pinion and ring gears and pinion bearing. The cage had fractured and the roller bearings were flat spotted. Diff fluid had burnt smell. The whole bearing fell apart when the tech pulled it out. He thinks the factory set it incorrectly.

 

Glad to learn you got your ride back, MLM!

Deysha

 

My experience was a little different than yours. I hope you have a successful outcome like I did!

https://themustangsource.com/f804/bl...ential-491623/

Just over 6000 mi. on the car now and no further issues.

 

Thank you to you and Alexis for your assistance and for checking in with the dealer on my behalf. I'll be in touch if there are any further concerns.

 

I hope so too! To some extent the delay was due to the holidays. Just happy to have the car back and happy that there's still no salt on the roads.

 

Awesome! Thanks, MLM!!

Deysha