Shell Helix Substitute

I know some people use oil other than Shell Helix 5w-40 in their 360's, and am just wondering if their is any conclusive information that shows that running something like Mobil 1 0w-40, or Mobil 1 5w-40 Truck and SUV is bad. I would guess there is no problem with running different oil as long as the viscosity is similar, but just thought I'd ask you guys. Shell Helix is a pain to find, and it's a hassle to take the car to the dealer for something simple like an oil change. If I could use Mobil 1, I could do an oil/filter change for less than $100. Thanks.

 

The car is a 99', so warranty is not an issue. So 0w-40 Mobil 1 is OK? Anyone use it? What about the 5w-40 Truck and SUV? Does the truck and SUV part mean anything, or is it just a marketing technique? Thanks.

 

That's what I was thinking. I'll give Mobil 1 0w-40 a try when the time comes in about 800 miles. I would think the slightly lower cold weight would help prevent wear at start up.