Automotive Engine Belt FAQs

Engine belts are simple but important components in modern vehicles. Each car engine belt plays a key role in powering specific auxiliary components. Whether you’re managing a shop or maintaining a fleet, understanding the different types of automotive belts helps you make more informed replacement decisions and avoid costly breakdowns.

Types of Car Engine Belts

Your vehicle may have one or more belts, depending on its age and engine design. The most common engine belts include:

1. Timing Belt

A timing belt is a toothed belt located behind the timing cover. It runs on camshaft and crankshaft sprockets. Its job is to keep the camshaft perfectly synchronized with the crankshaft so that engine valves open and close at the right time.

Modern engines often use timing chains, but many vehicles still rely on a timing belt, which typically needs replacement around 90,000 to 110,000 miles. We always recommend replacing the water pump at the same time -since both parts have similar lifespans.

You can shop our OE-quality Timing Belt and Water Pump Kits for complete solutions. Read more about the benefits of replacing timing belts and water pumps at the same time here.

2. Fan Belt

In some engine layouts, the fan belt powers key cooling system components like the water pump, radiator fan, and even the A/C compressor. If the fan belt fails, the engine will overheat – leading to serious damage.

While newer vehicles tend to use serpentine belts for this function, older engines may still rely on a separate fan belt. Regardless of the layout of your vehicle, regular car belt maintenance checks can help prevent breakdowns.

3. Alternator Belt

A separate alternator belt keeps the battery charged when a serpentine belt isn’t used. Depending on the engine’s design, this drive belt may also power the power steering pump. If the alternator belt fails, the battery won’t recharge while the engine is running, which may result in a flat battery and a stranded vehicle.

4. Serpentine Belt

The modern serpentine belt – also known as a drive belt or accessory belt – is a long, ribbed belt that powers multiple engine components with a single loop. This can include the:

Alternator
Power steering pump
Air conditioning compressor
Water pump

The serpentine belt runs off the crankshaft. Most last 60,000 to 100,000 miles. If fraying or cracking is seen, the belt should be replaced. Knowing the signs of a bad serpentine belt is key to preventing on-road failures.

How Engine Belts Have Changed Over Time

Automotive belts have evolved to be more efficient, durable, and capable:

Serpentine belts replaced multiple old-school V-belts
Materials have improved, increasing lifespan
Belt designs changed from narrow V shapes to wide and ribbed
Timing belts and tensioners are now engineered for quieter and smoother performance

What Are The Different Types Of Belts Used In Car Engines?

The most common engine belts include:

Timing Belt – syncs the crankshaft and camshaft
Serpentine Belt – powers accessories like A/C, alternator, power steering
Fan Belt – runs cooling components in older vehicles
Alternator Belt – charges the battery if a serpentine belt does not drive the alternator

How Do I Know If One Of My Car’s Belts Needs Replacement?

Watch for these symptoms:

Squealing noise, especially at startup
Visible cracks, fraying, or glazing on the belt
Warning lights on the dash (battery light, overheating)
Abnormal accessory performance (weak A/C, dim headlights)

Learn more about understanding timing belt failure here.

How Often Should My Car’s Belts Be Inspected Or Replaced?

Most shops recommend:

Inspecting belts every 10,000 to 15,000 miles
Replacing serpentine belts every 60,000 to 100,000 miles
Performing timing belt replacement around 90,000 miles

Always check your owner’s manual and follow manufacturer-specific guidelines.

What Happens If A Belt Breaks While Driving?

If a serpentine belt or fan belt fails, engine accessories will shut down, potentially causing the engine to overheat or the battery to die. A broken timing belt can lead to catastrophic engine damage in interference engines.

Learn more about what happens if a serpentine belt breaks here.

Are Timing Chains Better Or More Reliable Than Timing Belts?

Timing chains generally last longer and require less maintenance, but they’re heavier, noisier, and more expensive to replace if they fail. Timing belts are quieter and cheaper but must be replaced at regular intervals.

Are There Any Warning Sounds That Indicate A Belt Issue In My Car?

Yes. Most belts will exhibit several symptoms before complete failure, so listen out for:

High-pitched squealing noises
Grinding or slapping sounds from the engine bay
These could signal a loose belt, misaligned pulley, or worn belt tensioner.

How Much Do Belts Cost?

Prices vary by belt type and the make and model of the vehicle, however, the prices below are a rough indicator of what the various automotive belts cost:

Serpentine belts: Typically $50-$100
Timing belts: Alone, typically $50-$100, kits with a water pump can be a few hundred.
Fan/alternator belts: Usually under $75

Can I Replace Belts Myself?

Yes, fan belts, and alternator belts are often DIY-friendly with the right tools. Just be sure to follow torque specs and routing diagrams.

Timing belt replacement, however, is complex and usually requires special tools. Improper installation can cause major engine damage, so we recommend professional assistance unless you have the right equipment and mechanical knowledge for the job. For more information on timing belt replacement, click here.

Where Should I Buy Belts?

For mechanics, shop owners, and fleet managers, GMB is your trusted source for premium-quality automotive belts. We offer:

OE-spec parts engineered for durability
Complete timing belt and water pump kits
High-quality serpentine belts, drive belts, and more

GMB is an industry-leading manufacturer of OE and Aftermarket automotive products since 1943. With decades of experience producing high-quality automotive engine belts, we have OE specification replacement parts for many vehicles. Check out our full range of OE-quality parts:

If you suspect an issue with your timing belt or need a quality replacement, check out our catalog or contact our team for expert advice!