Just a normal guy here. Trying to keep my head above water after child support for my 12 year old. Keep my cars 10 years plus and 175K miles plus. Bought a Honda Element after my 1993 Subaru Legacy got KO'd while parked. I have a routine of changing my oil and filter every other month at ~1.5K or less. I perform most routine maintenance at 1/2 the time period or mileage of the manufacturer's recommendations. I had been running 5W50 Castrol Syntec in the Subaru without problem that I got at Walmart for $2 a quart. No analysis and no worries. A friend of mine that has a S2000, nice car, turned me on to the site. You guys have made me nuts!!!! I would have run the 24 quarts of Syntec 5W50 I got at Walmart without concern. Should I run the 5W50 in my lawn mower forever and get some Exxon 5W20 Superflo for my Element. Can I mix the 5W50 with 5W20 for my Element? Can I run the 5W50 in the summer in the Element and 5w20 in the winter? Can I run the 5w50 year round? Advice appreciated!!!