So, I just got my bottle of Auto-Rx in today, and I want to make sure I do this right. For the cleaning phase, am I supposed to just leave the old oil in there, put on a new filter and add the Auto-Rx, or am I supposed to change the oil out to non-synthetic at this point? I know Im supposed to change the oil during the rinsing phase, but I don't know whether or not to change it during the cleaning phase. Thanx!

 

change to non synthetic and add the RX, then do another nonsynthetic after 1500, and then 2000 on the second batch of nonsythetic, then change back to synthetic