What is this???

I found this into the suction screen of the transmission and I drained the whole oil from the pan and got a bunch of similar stuff...
looks like metal to me since it got caught by the magnet.

The machine still run forward and backward lacks power though...

I found the oil in the pan to be thicker than it should be. The old owner probably put high viscosity motor oil cause it was way too thick!

The black piece looks like it's made of rubber, a seal probably.

We thought it was the transmission pump but after inspection seems to work as it should

Any idea?

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