Should you stick with the same brand every time you change the oil in your car?
My question is about different brands of oil. Should you stick with the same
brand every time you change the oil in your car? Does it harm the car at all to
switch brands, as long as they are the same viscosity? One new-car dealer tells
me to use his brand every time or the engine warranty won't be any good. This
sounds ridiculous to me, but he's got me wondering. -- Mitch
TOM: And people wonder why nobody trusts car dealers.
RAY: You're absolutely right, Mitch. That's complete bull droppings. You can use
any brand you want and mix them together as much as you want, and it will have
no effect on your warranty. All of the major brands of oil are substantially the
TOM: There are two things to look for. The American Petroleum Institute (API)
rates oils for a variety of properties. Those that meet the most recent
standards are currently labeled "SJ."
RAY: "SH" and "SI" are recent vintages, too, and they're fine for all but the
newest cars. So look for those API ratings.
TOM: The other thing to look for, as you say, is the proper viscosity. Check
your owner's manual and see what your car calls for. Most call for 5W30- or
10W30-weight oil. But some recommend specific viscosities for unusual conditions
RAY: Other than that, your only really important consideration is whether you
like the colors on the label.