Bad spelling aside (vicodin not vicadin), yeah this thread is ok for now as it is mainly about the MJ and how to keep smoking it and not really asking for advice on the opiates.

I don't know but I can use some common sense here. Since methadone clinics are tightly regulated and some doctors don't approve of MJ use I would guess that testing positive for THC would have negative consequences. I don't know if stopping for 10 days would be enough time either because everyone is different. Diluting may not be an option as it may dilute your methadone levels and you look like your doing something wrong.

Here's what I would do. Stop smoking until you get your first test. See if it is going to be unobserved, observed (an observed test would be where they watch the flow of urine leave the body and enter the cup) or monitored (used to secure a multi stall bathroom or sinks can't be turned off they are in the doorway of bathroom but not in the stall). If it is unobserved or monitored, stay clean of THC and make some clean from THC but not clean from methadone urine and freeze it. Then be prepared to sub for future drug tests. After about a year replace your supply of frozen urine.