ponyman

So I dropped the car off this morning to get my 4.10s installed. A couple of hours later I get a call from the guy who gave me some interesting news. Apparently my D/S (stock one) had some sort of oil leaking out of the differential end. He seemed a little concerned and I guess had called Ford and they said it has a hole in the end and is fine. But he took it down there to get more info. They said that leaking is bad and it needs to be replaced ($389). He then took it to a driveline shop he uses and they said they had never seen anything like that before. He also called another place and they confirmed that this is something new.

So we decided to put it back and I'll work on a solution (aka new D/S), but all agreed that I should have some time before it is an issue.

He said that the gears went it really easily and nicely and everything meshed up great and it was a really smooth install (apparently even at 30k my bearings were in just awesome shape and decided against needing to be replaced).

So here lies the end result, when they took it for a test drive it has a really weird clunking noise. So it is a cyclical noise changing with speed. They didn't know what it was, took the cover back off and everything was looking great, but they are still at a loss. So it is staying the night and they are trying to track down the problem. So until they figure out what it is, I'm not too concerned. The only thing we know right now is that you can take it up to any speed and decelerate and you can hear it (it is a very circular thump...thump..thump..<repetative> down to stop).

However, I am really confused about the oil/lube coming out of the end of my D/S. Has anyone ever heard of/experienced this? WTF, would be causing it? Could it be leading to the thumping noise?

harraid5711

i'm clueless about the noise, other than the gears not being set up well. is the leaking just a faulty pinion seal? did he put a new one in?

ponyman

The leak is actually coming from the D/S. I guess it is just oozing out of the hole (not the same viscosity of gear oil. They discovered it when pulling the D/S. They did replace the pinion seal during the install though.

guess Ford said there is a seal in the D/S that likely is gone and isn't serviceable.

Texotic

that's some scary sh*t IMO... i'd probably have flipped out.

harraid5711

whoa....our d/s has fluid in it?

robsimp

what new d/s do you plan on going with?

ponyman

I'm normally a flip out kind of guy, but in this case it wouldn't do any good. He was honestly working to figure it out. A lot of shops would have not even mentioned the D/S issue. So I am glad he did.

I guess so. It does have a CV boot, which I'm guessing htere is some grease under? IDK, I know Ford did some stupid thing with this D/S.

Well, I was thinking a Sypdershaft, but I wasn't planning on almost 700 bones right before x-mas. So I may have to just get one from newtakeoff.com I can get one for $120 (probably plus shipping)


All I know right now is that my warranty was up in Aug and now I have the most random failure ever (a leaky D/S). And a weird thumping, which looking through the shop manual at everything I'm wondering if it isn't the bearing in the D/S and the fluid was some how staying in and silencing the noise, but not it is gone so I have noise.

Blarg, every project on this car is a chore

HoorayBeer

have you noticed
any oil spots under your car when you parked before?

ponyman

Nope, not at all.

MustangGT0405

I would change the driveshaft first and see if the sound goes away. I have heard alot of people get vibrations with aftermarket shafts on decel. So a new DS might fix it.

Good luck