@upallnight the reverse works perfect, no slip at all. It only takes the transmission 2 - 3 seconds to engage the reverse but only when the oil is at operating temp. When in reverse it doesn't have any slip at all. Could it be a faulty solenoid? I've read similar issues with this type (6HP26X) that was caused by a sticky solenoid but only those symptoms where with cold temp. instead of operating temp like in my case!