I have about 900 miles on my son's S-10 Pickup (4.3 V-6) during the clean phase. We are about 2-3 weeks away for putting it down for the winter. I like to change the oil for the winter storage, but I'm afraid we won't have 1500 miles on the Auto RX cleaning cycle. Will it hurt it to leave it in or should I change it out (I'm guessing we'll have 1,200 miles into the cycle). THanks.