Hey Quick, cars do need their oil changed every 3K miles. Synthetic oils last a little longer. Usually in the 3-5K range. Most smart people who buy synthetic know to change it at 5K. Before the flaming starts, I'll re-list my credintials: ASE mechanic for 5 years, employed by the southeasts largest, highest volume Quick Lube specializing in "high dollar/high performance" vehicles. I'm an avid racer and have built countless engines for racing and daily use. I've received certification from Valvolines oil and research institute. I'm not saying this to boast or anything, but I know a thing or two about oils. The manufacturer of motor oil will tell you that their product does not stand up over 3K miles. Synthetic oils should hold up to 5K, but that's not a risk I'm willing to take. If it's worth it to me to use synthetic it's worth it for me to change it regularly. all that being said...It's not the brand or type of oil that matters, It's the quality and condition.
