I'm pretty sure it's against the law to tell a customer they HAVE to go to the Dealership for routine maintenance. Keep ALL (I MEAN ALL) receipts of stuff done elsewhere or at home and you're ok. You must do ALL services listed in the maintenance schedule, or the manufacturer can void your warranty, but you cannot be told where to have the stuff done. But, if there IS an issue later, they will ask for proof of services to show proper maintenance. I've had portions of customers' vehicle warranties voided when they come in at 80k with no records of trans fluid changes and a new tranny is needed. If there's a question of what paperwork to keep- KEEP IT ALL! There's a "convenience factor" in going to the dealer- it's all right there, it's all OEM stuff, and sometimes they may find something to fix while the car is still covered. But, it's always more expensive. I've had customers deal with my place until the warranty ends just b/c we keep all records and such, and we're $5 more than Jiffy Lube
while using OEM Filters and gaskets and such. But really- it's YOUR decision, not the dealers'.