I just pulled this out of my rear differential. How screwed am I?

[apatter8]

A little background info:

Two weeks ago I took my car to Road Atlanta for my first ever track day. Everything went great, until my last session of the day. Halfway through, I smelled a foul odor and was immediately black flagged along with the Viper in front of me. They checked out both cars briefly, parked the Viper and sent me back out. I still smelled the odor for the remainder of my session (2-3) laps.

Afterward, one of the track officials came over and said that although they parked the Viper, he now was pretty sure the issue was with my car. Said I probably just scorched the rear differential fluid, and I should change it out at my first chance. I drove my car home just fine.

So my car sat parked for the last two weeks while I waited on my redline oil and gaskets. Well today I finally got around to draining my fluid, and after draining I found this lodged in the drain port:



Whatever it is, it's magnetic. What broke?

[40 to 332]

Was there any evidence of damage to the drain plug itself … since IIRC it is fitted with a magnet? Could it be that the magnet sheared off some how?

[POS VETT]

The drain plug has a magnetic insert. What caused it to separate? What does the fluid like? Can you snake in a boroscope and inspect the teeth?

[apatter8]

Originally Posted by 40 to 332

Was there any evidence of damage to the drain plug itself … since IIRC it is fitted with a magnet? Could it be that the magnet sheared off some how?

I was hoping there was a small chance that's all this was, but I've never seen a picture of the plug removed. There's definitely no magnet attached to the end of my drain plug.

[apatter8]

Originally Posted by POS VETT

The drain plug has a magnetic insert. What caused it to separate? What does the fluid like? Can you snake in a boroscope and inspect the teeth?

The fluid looked exactly like I thought it would; oem fluid with 40k miles on it. I did not see any metal shavings in it though. I do not have a boroscope, maybe I can borrow one from Advance/Auto Zone though.

[apatter8]

Here's picture of it alongside my drain plug. Sorry for the crappy cell phone pictures.

[40 to 332]

Well, there you have it … the magnet popped out of the housing. I suspect it would have simply remained on the bottom of the diff housing. If the fluid looked unremarkable, you may be OK. There's no evidence from the picture of the magnet that any chunks of metal were flying about. The residue on the magnet looks pretty normal for fluid with that much mileage on it.

[40 to 332]

Guess I should have asked: Were there any solid bits/chunks of metal on the magnet?

[apatter8]

Yeah, there are some smaller chunks of the magnet attached. Looks like it twisted off, producing some fragments in the process. Still not sure how this happened.

[chops]

you might be able to claim powertrain warranty...

[SouthArk370Z]

If the chunk is magnetized, then it's probably the plug insert. I don't recall there being any other magnetized parts in a differential. I'd make sure there are no parts of the magnet stuck to ferrous parts before putting it back on the road.

[juld0zer]

that's the magnetic insert. It's exactly that size and since it's missing off your drain plug then there's little doubt.

It's not a strong magnet though, so it probably has little ability to hold chunks of metal

[nis350]

check out post #27....

Maybe it came off due to the heat?


DIY: Rear Differential Oil Change

Originally Posted by apatter8

I was hoping there was a small chance that's all this was, but I've never seen a picture of the plug removed. There's definitely no magnet attached to the end of my drain plug.