Most Dealers actually use a Toyota branded Semi-Synthetic 10w30, made by caltex specificly for Toyota, but agree 100% service history is a massive factor. Min 15k/1year between services, but more often is better. A few other issues VVTI controllers (brief rattle on start up mainly when cold).Steering intermediate shafts (clunking noise from steering, not a safety issue just annoying)Leaking water pumps (look for any pink chalky residue in the engine bay