One lesson I learned. The dealers may miss things they should know about. This forum supplies a lot of information and knowledge about our 4Runners.
Little things I have run across. I was told that Toyota has no zerks, any more -wrong. They are not lubing the zerks on new 4x4 Toyotas -wrong.
I use Red Line oil and was told that 'stuff like Red Line, Mobil 1 and Amsoil' could cause warranty problems - wrong. I was also told that they use 10w-30 vs 5w-30 because they have better 'local knowledge' than Toyota - wrong again. They also tried to sell me a silicone spray for my paint and oil and gas additives. They said these made all the difference in a new vehicle - wrong.
I was told that the dealer was the only place to get the wheels balanced -wrong, Discount Tires has the right stuff for the center mount wheels. They charge 4 times the Discount Tire price, plus Discount tire will, for a couple of bucks more than their one time price will sell you a lifetime balance.
I was told that, although the severe duty oil change interval was 5k that they like to do all their oil changes at 3k because they have better 'local knowledge' than Toyota -wrong.
I had my sunroof repaired under warranty. It was a know problem and there is a repair kit. The problem came back. When we test drove my 4Runner is was quiet until we hit little, sparp bumps and then it rattled, open or closed. The jerk told me that the warrany did not cover the noise if I had to provoke it by driving over bumps (like the dots between lanes on the freeway). I know have to find another dealer. When they brough my 4Runner up to the service line, to return it to me, they reved the engine way up and spun the tires wth a dead cold engine, things I don't do.
My advise, lean all you can about periodic/preventive maintenance. Any major that I don't want to do is going to an independent mechanic. I just can trust the dealer, any more.