My aunt is the worst I know. She has a 2004 Toyota Solara with a 2.4L 4cyl with almost 200,000 miles, she has owned the car since it had about 160,000. I checked the dipstick & it was 1.5 quarts low & the oil was nasty pitch black. She told me she got the oil changed at the local Valvoline place every 4,000-6,000 miles, so I was like okay that's not bad. At the time I checked the dipstick, she had over 8,000 miles on this change. I ran her plate number in Carfax & she has been going 10,000-12,000 miles on Valvoline bulk conventional & cheap Valvoline filters, she lied. I changed the oil with Mobil Super High Mileage SynBlend & a FRAM Extra Guard. I told her to bring it back to me in 3,000 miles, I put a sticker on the windshield. We will see if she does. The oil I drained out was nasty black & thick. Also, one time she said there was grinding when she braked after she got new tires put on. I looked & the brake pad was completely gone, caliper was grinding the rotor. So new brake pads & rotors.... the car still runs excellent & the transmission shifts smooth for the miles. I told her she needs to get on top of the oil changes or this car will be dead within 40,000 miles max.