Are there really any differences in modern lubricating oils? I mean, as long as you use the proper weight of oil and it is of good quality, are there any real differences? Aside from the advertising hype, take for example, my neighbor has a big John Deere tractor that costs over $100,00.00 and he use Rotella oil for it and feels that if Rotella protects that huge investment it is alright to use in his autos and trucks.
Thanks for anyone's help.