Auto Parts Car

DIY or shop

Which car jobs you can do yourself, and which to leave to a shop

Some jobs need nothing more than the owner's manual and ten minutes. Others need training, special tools and a lift. Here is a general way to sort them.

Common parts by job type

The meter on each tag shows who usually does the job. Red tags are safety-critical. Your own car may be easier or harder than the typical case, so read the manual before you start.

No. 01 Safety-critical

Brake pads and rotors

What it does
Pads clamp a spinning rotor to slow each wheel.
Watch for
Squealing, grinding, a pulsing pedal or longer stops.
Shop job

No. 02 Safety-critical

Brake fluid

What it does
Carries pedal pressure to the brakes at each wheel.
Watch for
Low level, a soft or sinking pedal, a warning light.
Shop job

No. 03

Engine air filter

What it does
Cleans the air the engine breathes in.
Watch for
Visible dirt or debris when you lift it out.
DIY-friendly

No. 04

Timing belt or chain

What it does
Keeps the engine valves in step with the pistons.
Watch for
The replacement point in the maintenance schedule.
Shop job

No. 05

Oil filter

What it does
Traps grit and metal particles in the engine oil.
Watch for
Usually changed along with the oil.
Some skill

No. 06

Serpentine belt

What it does
Drives the alternator and other engine accessories.
Watch for
Cracks, fraying, glazing or a squeal at startup.
Some skill

No. 07

12-volt battery

What it does
Starts the engine and powers electronics when it is off.
Watch for
Slow cranking, dim lights at startup, corrosion.
Some skill

No. 08

Cabin air filter

What it does
Cleans the air that comes through the dash vents.
Watch for
Weak airflow, musty smells, fogging windows.
DIY-friendly

No. 09

Wiper blades

What it does
Clear rain, snow and grime from the windshield.
Watch for
Streaks, skipping, chattering or torn rubber.
DIY-friendly

No. 10

Headlight bulbs

What it does
Light the road ahead and let others see you.
Watch for
A dark or dim lamp, or a dashboard bulb warning.
Some skill

No. 11

Tail and brake lights

What it does
Show your position and warn drivers when you brake.
Watch for
Ask someone to check them while you press the pedal.
DIY-friendly

The three levels

DIY-friendly

Jobs that need few or no tools, don't involve lifting the car, and have low risk if something goes slightly wrong. Examples include wiper blades, engine and cabin air filters, many tail light bulbs, topping up washer fluid and checking tire pressures.

Some skill

Jobs that need basic hand tools, some care and sometimes a safe way to raise the car. Examples include oil and filter changes, many headlight bulbs, serpentine belts on some engines, and 12-volt battery replacement on cars that don't need the battery registered.

Shop job

Jobs that are safety-critical, need special tools or training, or can cause expensive damage if done wrong. Examples include brakes, timing belts, fuel system work, suspension and steering, airbags, air conditioning refrigerant, and anything on a high-voltage hybrid or electric system.

Questions to ask yourself first

  • Does the owner's manual describe this job for owners?
  • Do I have the right tools, including a torque wrench where bolts need a set tightness?
  • Will I need to raise the car? If so, do I have jack stands rated for it and a flat, solid surface?
  • What happens if I get it wrong? A loose wiper blade is an inconvenience. A loose brake caliper bolt can cause a crash.
  • Can I dispose of the old part and any fluids properly?
  • Will the car need programming, a reset or a test drive by a professional afterward?

Raising a car safely

Never work under a car held up only by a jack. Jacks can slip or fail. Park on firm, level ground, set the parking brake, chock the wheels that stay on the ground, lift only at the points shown in the manual, and support the car on jack stands rated for its weight before you go underneath.

Working with a shop

When you take a car in, describe what you notice instead of guessing the cause: what the symptom is, when it happens, and whether it is getting worse. Ask for a written estimate before work starts, ask to see or keep the old parts, and keep the invoice with your service records. Look for technicians who hold recognized certifications for the type of work, and ask how the shop warranties its parts and labor.

If you plan to bring your own parts, ask first. Some shops won't fit customer-supplied parts, and others won't warranty the labor when they do. The OEM and aftermarket guide covers part choices, and the safety page covers the warning signs that mean a car should not be driven.