Maintenance schedule VS Dealer's schedule

OK, so here goes....sorry if I rant on...I'll try to stay on subject. Are we supposed to do the scheduled maintenance that our user manual lays out for us or am I supposed to believe my dealer and "his version" of what the schedule should be? My dealer's time line is SOOOOO old school....oil change every 5K kms, and they wanted to do my breaks, my diff's transfer case etc that THEY SAY is needed cause they are working with the manufacturer and it's been proven....BLAH BLAH BLAH!!....isn't the owner's manual developed by Dodge? shouldn't they know what's what?

I've been doing my oil changes every 8k kms with Amsoil....and my truck only has 22k KMs on it....should I really have to do brakes, diff maintenance and about another 500$-900$ worth of "maintenance" that they had scheduled at 5, 10, 15, 20 and now 25k kms?

I think they are just trying to gouge me...right? how many people have had their dealers try that crap on them?? Could they deny warranty if I don't follow THEIR maintenance schedule?

Ok....rant over!

Sylster