SOLVED: Found something a little concerning in my rear diff

Hey all, quick question that hopefully someone can answer. I changed my rear diff oil yesterday and found something stuck to the magnet on the drain plug that has me slightly concerned. Aside from the usual metallic grime (and one small shaving), I found what appears to be a small conical keyed washer, maybe 3/8" (or 9-10mm) in diameter. I'm not sure it was originally cone-shaped, especially since it seems that it was loose in my rear diff.

I lost it before I was able to take a picture, so I apologize for not being able to provide more information. Attached is a picture of a flat keyed washer. Does anyone have an idea of where it came from, or if it should be cause for concern?



*EDIT*
I found this thread, which seems to document a fairly similar situation to my own:
https://www.tacomaworld.com/threads/excessive-amount-of-metal-shavings-in-rear-diff.304241/
The original pics are no longer available, which is unfortunate. It seems half the folks think the metallic chunks are cause for concern, while the other half are convinced that they're simply shavings from the manufacturing process. @gearcruncher, what do you think?

 

I had a peek at the parts listing for your truck . I cant say I have ever seen a tiny 1 way washer in a Tacoma rear diff .
If I had to guess , I would say it was accidently dropped into the diff housing during assembly .

https://parts.olathetoyota.com/auto...niversals-and-rear-axle-cat/differential-scat

 

Thanks for the help, @gearcruncher! I’ll take another look and see if I can’t find the damn thing so I can confirm what it is (or was).

 

looks like something that was accidently dropped into the diff., maybe they tried to use it as the fill plug gasket and fell in the diff, somehow?

 

Start calling me Hawkeye. This is what came out of the diff.

 

I had those too, along with shavings, I bought my truck had 49k miles im sure the diffs/transfer/trans. fluids were never touched, also measured the rear diff fluid capacity was close to .50 qt. low and dingy

 

That looks like the back side of what comes out when you drill a hole.

It might have hung onto the threaded area for a while then broken off. It doesn't seem to have been through your gears, also doesn't look like bearing material.

You are probably ok, maybe change the oil a little sooner than normal just to check up and have piece of mind.

 

That sounds feasible. Like when the factory drilled the hole for the vent.

 

Dude. How the hell did you spot that tiny thing? Thanks for locating it.

@gearcruncher, do you concur with the drilling remnant theory?

 

To be honest I don't know. I saw this thread pop up so I thought I would go take a look and immediately spotted it.

 

Clean it off little and take a better picture, I can see what look to be heat from a drill bit showing through the backside. The 3 dark spots.

 

Yup , looks like a small peice of leftover casting

 

This is from a piece of 16ga or 1/8" I think, I have a bunch of these from working on stuff in the shop.

It was drilled fast with a spot weld bit. That's why mine has a deep center hole and lots of heat.

 

Thanks for the help, guys. Extra thanks to @EatSleepTacos a.k.a. Hawkeye for somehow finding that little not-a-keyed-washer in his driveway.

 

That's what this looks like. Dark on one side and has a little dimple in the middle, barely broken through.

edit: it only looks a little wrinkly because it was on the garage floor while we continued working and got stepped on, etc.