Ok, one last question about my old plumbing. LOL.

I did some wash yesterday. After I dried all my stuff, I noticed stains and such on alot of my clothes. Looked almost like grease stains.

My question, is it possible for waste water that was just spun out of the washer, to wash back in? Its a pretty new washer. Every once in awhile, if it doesnt spin long enough, you can hear the water comin back down the pipes. But I never see it fill back into the tub of the washer.

Do these newer washers usually have a trap or something to keep water from refilling?
I just wanna make sure these stains arent from any type of nasty backwash, since it sits in the basement almost right under the kitchen.
Thanks!

Im not worrying about repairs in the long run cause though my family is staying here, I am moving overseas. So I will let them worry if they wanna fork out the money for repairs. I just cant afford it.