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The Dayco Poly Rib Serpentine Belt (6PK1550) is a precision-engineered replacement belt designed to deliver consistent performance and long-lasting reliability. Developed for modern passenger cars and light-duty trucks, this serpentine belt utilizes Dayco’s advanced W Profile EPDM construction, providing superior flexibility and durability in high-mileage or demanding drive conditions.
As the original developer of the multi-rib serpentine belt, Dayco continues to lead in OEM-grade engineering and performance. This belt is built to conform to worn or slightly misaligned pulleys, reducing noise while maintaining consistent power transmission across engine accessories such as the alternator, water pump, power steering, and air conditioning systems.
Constructed with aramid-reinforced EPDM compounds, the Dayco Poly Rib serpentine belt exceeds SAE J1459 and SAE J2432 standards, offering resistance to extreme temperatures from -45°F to 212°F (-42.7°C to 100°C). Ideal for both daily drivers and professional technicians seeking a dependable, OEM-quality replacement solution.
Features and Benefits:
Manufactured from aramid-reinforced EPDM compounds for superior strength and heat resistance
W Profile rib design adapts to worn or misaligned pulley systems
Reduces belt noise and vibration for smoother operation
Meets SAE J1459 and SAE J2432 standards for OEM performance and reliability
Designed to withstand operating temperatures from -45°F to 212°F (-42.7°C to 100°C)
Engineered and tested for high mileage and demanding conditions
Dayco Products
Dayco Products is an OE manufacturer that designs, manufactures and distributes a broad range of drive belts, hoses, tensioners and pulleys for the automotive, trucking, agricultural and industrial markets.
BMW:
328i (1996–1997), 328is (1996), 528i (1997), 545i (2004–2005), 550i (2006–2010),
645Ci (2004–2005), 650i (2006–2010), 745Li (2004–2005), 745i (2004–2005),
750Li (2006–2008), 750i (2006–2008), 760Li (2003–2008), 760i (2004–2006),
Alpina B7 (2007–2008), M3 (1996–1997), X5 (2004–2006), Z3 (1997)
Chevrolet:
Cruze (2012–2015), Cruze Limited (2016), Sonic (2013–2018)
Ford:
Ranger (1983–1990)
Honda:
Civic (2012)
Kenworth:
T680 (2023), T800 (2014–2019), T880 (2016–2020), W900 (2016–2017)
Peterbilt:
320 (2014–2017), 365 (2014–2018), 367 (2015), 384 (2014), 388 (2014),
520 (2019–2020), 567 (2014–2020), 579 (2014–2018)
Order Processing
All orders are processed and shipped within 24 hours of purchase (excluding weekends and holidays).
Orders placed after 3:00 PM EST may ship the following business day.
Shipping Methods
Customers select their preferred shipping method and speed at checkout.
Shipping times are determined by the carrier and cannot be guaranteed by us.
Tracking information will be provided once your order has shipped.
Shipping Coverage
If your package arrives damaged, please notify the delivery driver immediately and contact the shipping carrier to file a claim.
You must report any missing or damaged items within 14 days of delivery.
After this time, we cannot be held responsible for lost or damaged items.
Return Window
You have 30 days from the date of delivery to request a return.
After 30 days, we are unable to accept returns, exchanges, or refund requests.
Eligibility
Items must be returned in their original condition—unused, unwashed, and with all tags and packaging intact.
Certain products may not be eligible for return (e.g., special-order items, customized products, or perishable goods).
Items that have been altered, installed, or modified cannot be returned.
Return Process
Contact our Customer Support team to request a Return Authorization (RMA) before sending items back.
Once your return is approved, you’ll receive instructions on where to send the product.
Customers are responsible for return shipping costs unless the item was defective or incorrect.
Refunds
Refunds are issued to the original payment method once the returned item has been received and inspected.
Please allow 5–10 business days for the refund to appear on your account.
In some cases, a restocking fee may apply (if applicable, this will be disclosed during your return authorization).
