Basement sink water runs out, gurgles and sometimes splashes up into shower

Do you have a sewer system or a septic tank/ leach field deal?

Do you have a sewer system or a septic tank/ leach field deal?

1 sewer system, washing machine drains into sink, then gurgle, and sometimes splahes up into shower drain 2 feet from sinks. Particularly if recent soap suds in kitchen sink level above and dish washer used.
Other postings answer "vent problem"-so I am thinking of checking the roof vent with a small diameter auger snake.
Had snow here to-day so should wait. The roof vent has a cap on it,
sheplumb

Your vent has a cap on it

your vent has a cap on it
A "gurgle" indicates a blocked vent. If it's been capped you have found your problem. However, if the cap is a roof vent cap,(see image) remove it and send the snake down the sinks roof vent. Put out enough cable to reach the base and 20 feet more. Good luck, Tom

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