I switch between Mobil 1 and Castrol Syntec 5w30 and generally use the Mobil 1 filter.


Edit: I just realized the op started this thread in '06. I hope he decided on an oil before now.

 

Castrol Syntec 5w30 with Mobil 1 oil filter.

I use to use castrol syntec 0w30 euro verison for a bit, people say its fully syntec but it only comes in 0w30. I decided to change the weight to 5w30 since infiniti recommends it.

 

I switched from Mobile 1 to Castrol Syntec 5w30 with mobile1 filter.

I used mobile 1 for 45k miles and noticed alot of engine noise and now i just switched to castrol syntec at 60k miles and the engine sounds much quieter and runs more smooth.

 

Royal Purple baby

 

I will be running Amsoil when I get home.

 

Use to Amsoil but its getting hard to get in my area
So now I'm using 10W40 Castrol Syntec with Nissan OEM filters