Looks like I'll need to add oil after 3,500 miles. With the new GM standard, can I just use Mobile 1 5w30?? I know it meets the standard, but I don't want to mess with my warranty, especially with the turbo.
When you state "add oil" are you physically adding additional oil due to the oil level being low, or are you referring to changing the oil and oil filter? The reason I ask, is if you are simply adding oil to what came with your Regal, I wouldn't spend the additional money to add synthetic. If you are actually going to change the oil, then Mobil 1 fully synthetic 5w 30 motor oil for your Regal is fine. Obviously more expensive than conventional oil, but I can understand spending a bit more for the synthetic. I just had the third oil change performed on my Regal last week and I switched to Mobil 1 fully synthetic 5w 30 oil. As stated in the owner's manual, this oil is can be used on the 2.4 liter ECOTEC, assuming this is the engine you have in your Regal. If you have the 2.0 turbocharged ECOTEC, then the aforementioned oil is recommended and I believe is the oil this engine should have arrived with from the factory.
Regardless, if you are changing the oil yourself and plan to go to the Mobil 1, it should not affect your Regal's warranty. Just make sure you keep all receipts for the materials you purchase to do the oil change... oil and oil filter.
I hope my long-winded explanation answered your question and was helpful.