The original specifications called for 20w50 oil in warm climates. Lubricants have improved in the 20 years since so 5w30 may be ok but I've used Mobile One 15w50 synthetic ever since it was available and have never experienced a problem. Slick 50, in my opinion, would best describe the marketing guru that sells it. If engine durability could be had in a bottle the auto manufacturers would have gobbled it up years ago. Warranty costs are a major detriment to the profitability of the car companies and they'll do anything they can do to reduce that cost. I don't think additives like Slick 50 will do any harm but I do feel they're a total waste of money. Bruce Benson > I went and bought 7 quarts of Penzoil 5W30 SYNTHETIC oil.... > > Is synthetic OK to put in a delorean, or is regular oil better? > > What IS the correct weight? (I live in New Mexico, where it is warm). > > Every car I have I have put Slick 50 in, and they all last over > 190,000 miles.... is it safe to put in my Delorean as well? > Mike >