Hi guys, My wife drives a 2006 Mazda 3 Sport with the 2.3 litre. Is it common for the valves to tick a bit on these in the morning? I've heard it twice now. the car only has 50K on it, I'm running Amsoil XL 5w20. I've heard these engines use 5W30 as well, in this case, should I make the switch? I'm not blaming the oil, because under normal operating temp, you can even tell the engine is running, and it sounds beautifull and smooth when you punch it. Othe than the cold valve tick, which is really noticeable, it runs really nicely. Any thoughts? other Mazda owners?