The valve train oiling channels and lubrication design largly influence the oil weight specification as do EPA fuel economy targets by the mfg. Do not use anything other than 5W-30. All synthetics from Mobil, QS, Valvoline, Pennzoil etc. are very similar. All are excellent. Just don't switch brands often because the engine becomes conditioned to a certain brand's additive mixture. When you change brands it takes a couple of intervals to become acustomed to the formula - consumption can increase as well.
