The following tips and indicators will help you educate your customers on their vehicle's drive belt. From wear and tear warning signs to replacement guidelines, this is your one-stop guide to drive belt maintenance.
Belt by the numbers
As little as 5% of surface wear can cause a belt to slip
If 2 cracks are counted in a 2-inch surface section (rib), then the belt has already used up 80% of its lifespan
#1 cause of noise: belt misalignment
1 broken belt = 1 broken down vehicle
Assessing your customer's vehicle performance
The top clue is noise, a squealing during startup or when parking. Another clue is speed sensitive whining or growling
Replacing components will ensure the best belt performance. (that's how we roll)
within a pulley can cause extensive tension, increased noise and vibration
Buzz = likely overrunning alternator decoupler failure
Chirp = misaligned or worn out belt or pulley
Squeal = might be low tension or pulley drag
Types of belt wear
These parts have a service life of 60,000 to 90,000 miles. Belts break down due to heat and external conditions. Made up of a surface side (rib) and edge portion (flanks), all portions of a belt should wear uniformly. However, that doesn't always happen.
Rib wear: High mileage, misalignment, defective pulley bearing
Glazing: Shining/hardening of the belt due to aging
Backside damage: Most likely caused by a defective pulley
Misalignment: Can cause a noticeable noise. Bad alignment can kink or twist a belt, accelerating deterioration
Abrasion: Excessive slippage or foreign debris in the drive
Improper install: This happens - unfortunately
Regular belt inspections will save your customer's vehicle
Check for irregular movement, damage and other indicators that belt performance is suffering.
Tell me more about belt slippage. Friction builds between a belt and drive system components; it's like a tire rotating down a road, wearing away the tops and the sides. A belt begins to slip (catching suddenly in less worn portions) when grooves of the belt and grooves of the pulley no longer connect. In other words, belt tension is critical. Weak tension results in belt slippage, which damages the belt.

Even if a bad belt can function, it can impact power steering, making a vehicle hard to drive. It can cause overheating, eventually leading to a breakdown.

Check it right the first time:
High mileage

Belt noise

Erratic belt movement, poor track

Tensioner out of range

Belt wear

Tensioner stuck or jammed

Tensioner damaged or worn
Ensure the drive belt system is inspected each time the vehicle is serviced. For customers, now is always the right time to change a bad drive belt system.