My whole body is sore itake methadone could that be my problem or could it be my liver from hept c?

Or other: Is very hard to know what is causing your symptoms. It may be unrelated. Many people with hepatitis c complain of fatigue but not usually body aches or pain. You may develop body aches if you are reducing the dose of methadone.

Hepatitis C and pain: Hep c can cause joint and muscle pain. Methadone is used for pain treatment and for opioid addiction. Methadone treatment is generally not associated with muscle pain. It could be if you have skipped dosing and have withdrawal or if after long term use you develop opioid induced hyperalgesia, which is a condition where the opioid pain medication (in this case methadone) actually causes more pain.