Another oil debate. I'm no expert but I'd side with Jerry about the viscosity unless you can find a synthetic with a higher cold viscosity. I'll have to respectfully disagree with Kevin about there being no benefit. Everything I've read indicates far superior wear protection with full synthetic. I use 15W40 Delvac oil in my 38 and 53 for the higher cold viscosity but full synthetic in my 18 year old pickup (since my first oil change). I'm still using dino oil in my Charger since that's what's called out in the service contract. When the service contract is up I'll be switching to synthetic in it as well. I use Walmart brand synthetic. It's MUCH cheaper than the name brands and meets the same spec. The Walmart brand full synthetic is also cheaper than dino oil in 5 qt. cans.

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