Keep every accessory pulley spinning under steady tension with the Dayco accessory drive belt tensioner assembly, part number 89603. This automatic belt tensioner assembly applies spring-loaded force to the serpentine belt so it stays properly seated and tracking across the accessory drive. It drops in as a direct-fit replacement for many Ford, Lincoln, Mazda and Mercury applications, including the 2011-2019 Ford Explorer 3.5L and 2007-2018 Ford Edge 3.5L / 3.7L — see the Buyer's Guide tab for the full list of covered vehicles and engines.
Signs this Dayco drive belt tensioner may need replacing include belt squeal or chirp, a fluttering or vibrating belt, and a rattling noise from the tensioner. If a worn tensioner is the cause, this assembly replaces it.
Interchange: 38485 · 49450 · 999419A · BT4Z6B209B · BT93 · BT97
This part cross-references / interchanges with the following part numbers:
What is a serpentine belt tensioner and what does it do?
It is a spring-loaded pulley assembly that applies constant tension to the serpentine belt, helping keep it seated and correctly tracking across the engine accessory drive.
Does the Dayco 89603 fit my vehicle?
It is a direct-fit replacement for many Ford, Lincoln, Mazda and Mercury vehicles with V6-3.5L or V6-3.7L engines. Check the Buyer's Guide tab to confirm your exact year, model and engine.
Is this an automatic tensioner?
Yes. It is an automatic type, so an internal spring self-adjusts to maintain tension on the belt rather than requiring manual adjustment.
What are the pulley specifications?
The assembly has one flat pulley measuring 70 mm in diameter and 25 mm wide, with a counter-clockwise operating direction.
What are the signs of a failing belt tensioner?
Common signs include belt squeal or chirp, a fluttering or vibrating belt, and rattling from the tensioner. Diagnose the cause first; if the tensioner is worn, this assembly replaces it.
WARNING: These products can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
