After reading over the spec sheets for M1 and Chevron Supreme Synthetic in 10w-30 wt, (the one not branded as "blend", but rather the "true" synthetic, whatever "true synthetic" means anymore! ) it looks like the Chevron has a higher flash point, higher Kinematic Viscosity at 100C, and a lower pour point in winter. The higher flash point means a good deal to me since I have one of those Toyota V6 models. BUT, can the Chevron Synthetic last for a 5K drain in a Toyota V6? I'm currently using M1 10w-30 and will perform an UOA when the mileage hits 5K, but it's the price of M1 around here...$4.00 + TN tax is $4.50 per quart is the cheapest I've seen at WalMart. I know M1 has a strong following (and might asking for an uphill battle against using M1) but is there solid evidence that backs up the Chevron synth's numbers? Anyone else using this oil in conjunction with extended drains?