What synthetic oil do you run?

I run Amsoil XL series 5w-30 in both my Suburban and wifey's Altima. I use the Amsoil Ea oil filters as well. I've been running Amdoil for almost 3 years now and prior to that I used Mobil1 SuperSyn. The Altima has has Synthetic ran in it ever since the very first oil change at 3k miles. It now has 115k miles and still runs like new. I bought the Burban in 06 with 52k on it and ran Synthetic since day one. It now has 130k on it and you would never know it. I changed a valve cover gasket recently and the rockers had ZERO sludge on them, they look brand new.
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