I got one in 2 weeks ago. GM55A ordered through rock auto.
I looked inside and saw brown color. I my case is was an oil coating most likely from the production process.
it was blocking the outlet.
...pic... ...pic... ...pic... ..inside tank pic... I just installed a pipe plug in the outlet and poured some solvent in the tank and swashed it around. Cleared the outlet and made sure there was no loose material in the tank.
I think the tanks are tested with air.
