Some things are absolutely necessary, some can be a waste of money. If I took my car in every 12000 miles like the manual suggested, it would cost several hundred dollars every time; most of this is "inspection" of items that you can and should do yourself to avoid the poorhouse.
I. the oil and filter every 3000-5000 miles. Use the exact kind of oil the cap recommends, unless you live in a severe climate. Ultra expensive oils cost a lot more and may be beneficial if the car is very expensive or you drive it hard.
2. The transmission fluid needs changed about every 60000 miles. Some people swear to leave it alone forever, but it probably is better to change it regularly. It should be routinely inspected for color, and should be red if this is an auto transmission; if it gets brown or smells burnt, have it changed immediately. Do not let it go below the low mark, or way above. Manual trans cars, check oil at 60,000 and top off.
3. Power steering. Just keep your eye on the level, and check the input and output hoses, they are under pressure and can leak.
4. Air filters about every 12000 miles, check to see if you have a cabin filter, too.
5. Plugs, now usually last 100,000 miles, but not always.
6. Plug wires at 100,000 should be checked. If they are still flexible, I reuse them; you could use a continuity tester to see if they are internally broken, but you can tell by how the car runs anyway.
7. Battery. Keep it clean and connections tight. careful the bildup is hazardous to your eyes. Do not get this stuff on you or inside the battery. Wash off the whole area. Buy a cheap post cleaner and rough up the terminal ends every few years. After 4 years if the battery has not gone dead, start looking for one on sale and replace it yourself if you can. One I had lasted 6 years, but that was a record.
8. Replace the windshield wipers every year or two. They dry out and eventually will scratch the glass if you wait till they fall apart. You can get replacement blades cheaply.
9. Watch the air in the tire. Keep it inflated to about 30 psi; never let it go low, its dangerous and will wear out the tire. Rotating the tires can be costly, so check to see how they are wearing; if the fromt edges are getting thin, put them on the back. Rotating tires every 5000 miles will add life to them, but can cost more than you can buy an new tire for over time. Keep an eye on the air in the spare. And its a good idea to get the jack out and make sure you know how to use it before its midnight and you need to change a tire. Keep a flashlight in the glovebox.
10. Walk around the car occasionally to make sure all the lights work.
11. Brake fluid can deteriorate, when you need brakes, generally at 40,000 miles or sooner, they will add fluid. Thereafter look at it yourself. If you have a clear reservoir, make sure it is topped up. Consider a full flush of the fluid after 100,000 miles.
12. Watching the brake pads is pretty hard. You usually have to pull a wheel. Go to a parts store and ask to see a set of your pads and note the thickness when new, and where the minimum level is. That will give you an idea when it is time to change them. Any funny noise should be checked immediately. If you can see the brake rotors through the wheels, look at them once in a while, any gouges that appear indicate that the pads may be work out. Replace asap or your buying new rotors. Sometimes rotors are cheaper to replace than resurface, so ask first.
13. Front wheel drive has no rear end, but if not check the differential fluid when you check the transmission.
14. Front axles have rubber boots that cover the CV joints. Sometimes they break. There is not much you can do but replace them, usually the whole axle. One tip, though; don't turn the wheels all the way to to locked position either direction. This stretches the boots and hastens the cracking. Once they crack, the grease will spin out and then the joint will begin making noise. You could drive a while this way, but eventually will need to fix them because rarely the joint can break off. Then you have a problem and can lose steering or power.
15. Buy a can of spray lithium grease and squirt all the hinges every year.
15. but a can of upholstery cleaner and clean up soiled seats asap. If you have leather, get some saddle soap or leather cleaner. Nothing looks worse than cracked leather seats.
16. Invest in a full set of mats.
17. Wash the car a lot; spray underneath. Look for places that accumulate mud and wash them out. Mud with salt never dries out and eventually will rot the body.
18. if there is a rubber plug in the bottom of the spare tire well, pull it out, same with any on the inside of the fenders right behind the rear wheels. These let out water that gets in the trunk.
19. Get some armorall and wipe the weatherstripping and dashboard when you wash the car.
20. Always take the end space in the parking lot, at least you wont have to worry about someone nicking that side of the