I own a repair shop, and I’m about to tell you to do some of your own maintenance. That probably sounds backwards. It isn’t. The jobs you can safely do at home are the cheap ones, and I’d rather you spend your money on the work that actually keeps the car alive.
The line between the two isn’t difficulty. Plenty of jobs are easy to do and terrible to get wrong. The line is consequence — what happens if it isn’t done right. That’s the whole test, and once you see it that way the list sorts itself.
Why is a shop owner telling me to do my own maintenance?
Because an air filter is not where a shop makes its living, and because a customer who feels talked down to doesn’t come back. If you can swap your own cabin filter in four minutes in the parking lot, swap it. When the transmission starts slipping, you’ll remember who was straight with you about the small stuff.
There’s a second reason, and it’s more practical. People who touch their own cars notice things earlier. You spot the cracked belt, the weeping hose, the tire wearing on one edge — and you bring it in while it’s still the cheap version of that problem.
What I’d genuinely do yourself
These are low-consequence. Get one wrong and you redo it.
- Engine air filter. Clips or a couple of screws, and the housing is usually right on top. In Phoenix this one matters more than most places — see below.
- Cabin air filter. Behind the glovebox on most cars. If your vents smell like a garage floor, this is why.
- Wiper blades. They die of sun here, not use.
- Tire pressure. Check it cold, use the number on the door jamb sticker — not the number moulded into the tire sidewall. That sidewall number is the tire’s maximum, not what your car wants.
- Washer fluid. Buy the summer stuff. Water alone grows things and can freeze on a Flagstaff trip.
- Battery terminals. Corrosion comes off with a wire brush. Disconnect the negative first, put it back last.
- Reading your own fluid levels. Oil, coolant reservoir, brake fluid. You’re not topping anything up blind — you’re learning what normal looks like so you notice when it isn’t.
What I’d leave alone
Not because you couldn’t figure it out. Because the failure mode is expensive, or it hurts.
Brakes. Not a beginner job, and the consequence of a mistake is the one part of the car that has to work every single time. Torque matters, hardware matters, and you can’t see a seized caliper slide from the outside. If you’re not sure where yours are at, that’s what a brake inspection is for — it’s free here.
Anything under a car on a jack. A jack lifts. Stands hold. If you own stands and know how to use them, fine. If you’re reading this to find out whether you can, the answer is not yet.
Suspension springs. A compressed coil spring stores a serious amount of energy. This one genuinely injures people.
Air conditioning. The parts-store recharge cans are a bad trade. Most of the time the system is low because it’s leaking, and adding refrigerant treats the symptom for a few weeks while the compressor runs low on the oil that’s carried in that refrigerant. On anything 2015 or newer you’re likely looking at R-1234yf, which needs different equipment entirely — at that point it’s A/C work for a shop.
Timing belts, airbags, fuel system work. Different reasons, same answer.
The thing nobody mentions about doing your own oil change
You can do it. The mechanical part isn’t hard — drain, filter, refill. Two things usually make it not worth it.
The first is the drain plug. It goes into the aluminium oil pan on a lot of modern cars, and it wants a specific torque and usually a new crush washer. Overtighten it once and you’re buying a pan.
The second is the part that isn’t the oil change at all. When a car goes on our lift, somebody is underneath it looking at the whole underside — a weeping axle boot, a hose going hard, a tire wearing on the inside edge you’d never see with the wheel on. That’s the actual value of the visit. Do it yourself on ramps in the driveway and you save a little and give up the look — which is most of what you’re actually buying with an oil and filter service.
If you enjoy doing it, do it. Just get the car up on a lift somewhere once a year anyway.
What Phoenix changes about this list
We’re considered a severe operating environment, and that isn’t marketing language — it’s how the manufacturers classify it. It moves some of these jobs up the list.
Air filters, both of them, come round faster. Dust is constant here and a monsoon haboob will load a filter in an afternoon. If you drive dirt roads or you’re anywhere near construction, check the engine filter at every oil change rather than at the interval in the book.
Wipers die of UV, not rain. The rubber hardens and tears sitting in 110-degree sun. You’ll find out they’re gone during the first monsoon storm, at night, on the 101 — which is the worst possible time to find out.
Battery terminals corrode faster in heat. Heat drives the chemistry that makes batteries fail here in about half the time they’d last somewhere mild, and clean terminals won’t stop that, but dirty ones will make a healthy battery look dead. If it’s cranking slowly, get the battery and charging system tested before you buy anything.
Frequently asked questions
Will doing my own maintenance void my warranty?
No. In the US you’re allowed to service your own vehicle without losing the factory warranty. What you do need is proof — keep receipts for parts and note the date and mileage. If a warranty claim ever comes up, that record is what you’ll be asked for.
How do I know if a job is above my head?
Ask what happens if it’s wrong. If the answer is “I do it again”, have a go. If the answer involves the car not stopping, a spring letting go, or a part that has to come back off to fix it, leave it.
Do I still need the shop if I do the basics?
For the basics, no. For anything that needs the car in the air, a torque spec, or a diagnosis rather than a part swap, yes. Most people land on doing filters and fluids themselves and bringing it in twice a year.
Is there anything I should check more often here than elsewhere?
Tire pressure and both air filters. Pressure moves with temperature swings, and the dust here is relentless.
My car is due for a service but nothing feels wrong. Do I need to bring it in?
Sometimes the honest answer is no. Call us and tell us the mileage and what the book says — if it’s a fluid that genuinely isn’t due yet, we’ll tell you that instead of selling it to you.
If it’s above your head, come see us
Bring the car in and we’ll put it on the lift and show you what’s going on — photos, the actual part, what we’d do and what we’d leave alone for now. You can decide from there.
Jimmy G’s Automotive — North Phoenix
17217 N Tatum Blvd, Phoenix, AZ 85032
(480) 599-5111
Jimmy G’s Automotive — Peoria
8615 W Kelton Ln, Suite 306, Peoria, AZ 85382
(480) 932-3565
Mon–Fri 7:30 AM – 5:00 PM · Sat 7:30 AM – 4:00 PM · Sun closed