Blown Differential!

Ronin38

Blow all the things!
15 Year Member
Dec 18, 2010
7,111
4,309
224
Dayton, OH
2011 GT Premium, auto trans. 534 miles, NO mods at all yet.

Well, driving in to work this morning on the highway, I had a bit of an issue... Traveling 70 mph on Cruise, I felt a "tug", it felt like the car down-shifted. (This was on a flat, level road.) Shortly after that, a vibration started and quickly got worse, but there were no "bad noises". I though I had blown a tire, but the TPMS light was not on. I then noticed white smoke coming out the back. :eek:

I pulled over to the right shoulder ASAP, and got out to check the tires. They were all fine. Something did NOT smell good! I looked under the back of the car and saw black fluid dripping down from the rear end... :bang:

Called the tow truck and had it hauled to the dealer. They gave me a fairly decent '09 Focus for a loaner. (Not a bad lil' car, frankly.) They called this afternoon and said they think a bearing went out "or something", and it ate itself. Little bits of metal all over. They've ordered the replacement, and the parts should be in on Monday, I may actually have it back Tuesday. They said it is all covered under warranty, no problem. :D

Hopefully it's got that out of it's system and all will be good now! :nice:

I have NOT done any burnouts or donuts - seriously! I bought the car with 30 miles on it, and I put on most of those with 2 test drives! :shrug:
 
Picked up my car today! Only 2 business days, so that's not too bad. Made it home okay... haha. ;)

I did feel a slight vibration in the car while driving home, I hope that's not a bad sign. It seemed to be gone by the time I got home, though... :scratch:

Finally warm enough to wash it too, so it's back to it's original color! :nice:
 
I had the same problem but I was lucky to catch the noise prior to it getting as severe as yours. Ate the pinion bearing up but after being tore apart and replacing all bearings; it's been good since.
 
I have NOT done any burnouts or donuts - seriously! I bought the car with 30 miles on it, and I put on most of those with 2 test drives! :shrug:

There is the problem.....Mustangs must do burnouts to keep everything in working order.....lol

Glad to hear it got repaired with no problems. I always take some time driving with the windows open and no radio just to listen to the car for any odd noises.
 
There is the problem.....Mustangs must do burnouts to keep everything in working order.....lol

Let's just say that the new differential has been properly tested... ;)
I'm now at 120 mi. AD... "After Differential". :D

Glad to hear it got repaired with no problems. I always take some time driving with the windows open and no radio just to listen to the car for any odd noises.

I've hardly had the radio on at all since it was fixed! :nice:
 
Update - vibration issue.

Well, I have about 700 mi. on the car, and still have a small vibration at highway speeds. I also have an occasional vibration when slowing down (engine braking) from 40 mph or so. I took it back in to the dealer yesterday, and the tech. who fixed it the first time took the car for a test drive with me. He definitely noticed the vibrations, and they're going to take care of it.

I have a 2010 Sebring for a loaner this time. I actually liked the '09 Focus better... Plain, boring appliance car.

The Sebring is nice. Not thrilling, but nice. ;)
 
Got my car back today! :banana:

The service mgr. explained everything they did to find/fix the issue... quite a lot! They checked out the diff. and everything seemed okay there. Then they swapped my drive shaft with one from a brand-new Mustang off their lot. Tested both cars for noises and vibrations. Swapped the drive shafts back, tested again. Re-indexed (and then re-balanced) my drive shaft, inspected all the U-joints, and made sure everything was lubricated and tightened properly. During the course of all this, the technician, shop manager and service manager all drove each car checking for noises and vibrations.

Then when I got there to pick it up today, the service manager rode with me while I tested it out, also. I do think it's fixed this time. :D

The want me to "test it thoroughly" this weekend, and report back on Monday. I think I can do that... :nice:
 
The exact same thing happened to my '11 auto 5.0 stang about 2 months ago. It seems that problem boils down to the axle been overfilled from factory and in the process it'll spit the front pinion seal. You can read all about my issue in modular fords under VelR5.0 username. Everything started with a leak from the axle breather and they claimed is was a bad breather. But later on bang! Complete axle went out. Once replaced it started to leak again thru the breather so I took it back and finally they lowered the fluid a little bit and I drove from IL to TN and no problems so far. Btw the same thing happened to a brand new 5.0 in the lot when a customer went for a test drive! Imagine that! So no...you are not the only one and I expect to hear about more issues like this unfortunately. So folks keep an eye on oil coming out of the breather(axle vent), because this could spell disaster!

Good luck to all!

Epi
 
Epi- thanks for the note! Can you tell me where the axle vent is? This is my first Mustang. ;)

FYI: Prior to mine going out, I had NO fluid leaks anywhere. I park it in my garage on a clean concrete floor, and there were NO drips on it anywhere.
 
Epi- thanks for the note! Can you tell me where the axle vent is? This is my first Mustang. ;)

FYI: Prior to mine going out, I had NO fluid leaks anywhere. I park it in my garage on a clean concrete floor, and there were NO drips on it anywhere.

Ok. When you look underneath from the back is going to look like this:
-'--O--- the little vertical line is the axle vent on top of the left axle tube. Lol
 
The exact same thing happened to my '11 auto 5.0 stang about 2 months ago. It seems that problem boils down to the axle been overfilled from factory and in the process it'll spit the front pinion seal. You can read all about my issue in modular fords under VelR5.0 username. Everything started with a leak from the axle breather and they claimed is was a bad breather. But later on bang! Complete axle went out. Once replaced it started to leak again thru the breather so I took it back and finally they lowered the fluid a little bit and I drove from IL to TN and no problems so far. Btw the same thing happened to a brand new 5.0 in the lot when a customer went for a test drive! Imagine that! So no...you are not the only one and I expect to hear about more issues like this unfortunately. So folks keep an eye on oil coming out of the breather(axle vent), because this could spell disaster!

Good luck to all!

Epi

Thanks for the tip! I registered on that site and read the thread. I will print it out and take it to my dealer!

:nice:
 
Took my car to the dealer today for the leaky valve.

They said there wasn't much leaking this time, but it was still there (I didn't get to verify). They told me they put in 5 pints of fluid in there...(which makes me think they drained it all, then filled it up) and that was the factory spec, and then took a little bit out (?). I thought they would have just drained some out rather than drain/fill completely.

They also emailed engineer's at Ford and I guess there IS a new valve for this car, so they ordered it and will call me when it comes in.

That's it for now.