Just picked up my new Corolla Wagon today, 1.8 4cyl. The Service book advises NOT to change the factory fill during break in and to wait till first service. Explains sludging and importance of regular oil changes at 10k kms service interval (6.25k miles) to prevent, but no mention of using synthetic oils, viscosity prefered is 5W-30 but 10W-30 ok. There is an option to do extreme duty service at 5k kms which I shall do myself using Mobil 1 10W-30 (5W-30 not available in Australia) and have dealer perform 10k kms services. By the way the car is a delight and hopefully will last me forever!
Roger
Roger