This is most likely caused by a lack of venting on either your washing machine drain or sink. The gurgling noise you hear is actually air getting drawn through the water in the sinks trap as the...
Yes.
Unless it is going to a laundry sink (like in a basement) That is how they did
it back in the twentys,thirtys and fourtys in oklahoma. There are still alot
like that today.
Washing machines pump out a large volume of water and todays standards require a 2inch drain pipe. Bathtubs generally have a one and one half inch drain. So bathtub drain will have to be increased to...