What is this? And would it leak oil?

Dumb question, I know but still learning. I noticed some oil on the ground from my f150 2006 4x4 5.3L. It seemed to be leaking oil from what I have circled as red in this image. What is this? And does that make sense?

That’s a rubber plug on the bell housing for the transmission.

If the fluid is dark brown/black, the rear main engine seal is leaking.

If the fluid is red/dark brown/black, the transmission front seal is leaking.

Check the transmission fluid color.

If it’s still red, the engine seal is leaking.


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And that is not a 5.3 liter V8 engine. 5.4L maybe…

Totally meant 5.4. Not sure why I put 5.3

It was definitely dark brown/black

Check the color of the transmission fluid.

Is it the same color?

If so, either seals could be leaking.

And for yucks and giggles, take a screwdriver and pry the rubber plug out of the bell housing to see how much fluid runs out.

And put a pan under there.


So nothing came out when I popped the seal. Transmission fluid looks red when I just checked.

Do have to add oil between oil changes?

Or don’t you monitor the oil level between changes?


I haven’t had to add oil. This is the first time I spotted the leak and it wasn’t a ton. I had the truck running while I was working on the ac for 20 min. That’s when I noticed the small oil drops. Crawled under the truck and saw oil pooling to drip around that gasket. Then wiped everything down so I could better spot the exact spot of the leak


A vehicle that’s going on 18 years old, that’s pretty good.

For all we know, a valve cover gasket from above may be leaking that little iota of oil that runs down drips from that spot.

I wouldn’t worry about it.


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