You might want to try the industrial strength Drano first. Any blockage is probably a mix of soap scum and lint.
@Chrisinkingwood: I tried that this weekend. I can still only get about a pitcher of hot water down the drain so I am hoping it is right there(I know, wishful thinking). Right now I am doing laundry with the drain from the wash machine in a large rubber maid. I just wasn't sure if I needed 1/4, 3/8 or 1/2" and how long it should be...I have seen 25, 50, and 100 ft. I know 100ft is too much.
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