Keep the serpentine belt properly tensioned and every driven accessory spinning quietly with the Dayco drive belt tensioner assembly, MPN 89387. This automatic belt tensioner drops in as a direct-fit replacement for the 2005-2007 Cadillac CTS (V6-2.8L), the 2004-2009 Cadillac CTS and SRX (V6-3.6L), and the 2005-2011 Cadillac STS (V6-3.6L), where it is cataloged for the air conditioning belt position. It applies constant spring load to the belt so slack, squeal, and slippage are held in check across the accessory drive.
Automatic operation: self-adjusting design that maintains belt tension as the belt wears and stretches, rotating counter clockwise.
Single pulley: one flat pulley measuring 70 mm in diameter and 27 mm wide.
Belt type: built for serpentine belt drives.
Origin: Made in the United States.
Signs this serpentine belt tensioner may need replacing include belt chirp or squeal, a visibly fluttering or vibrating belt, and a worn, seized, or noisy pulley bearing. If a failed tensioner is the cause, this assembly replaces it.
Interchange: 38419 · 49389 · 49390 · 38418 · 999689A · 999690A
This part cross-references / interchanges with the following part numbers:
What vehicles does the Dayco 89387 tensioner fit?
It fits the 2005-2007 Cadillac CTS (V6-2.8L), 2004-2009 Cadillac CTS and SRX (V6-3.6L), and 2005-2011 Cadillac STS (V6-3.6L). See the Buyer's Guide tab to confirm your vehicle.
Is this a serpentine belt tensioner?
Yes. This is an automatic tensioner built for serpentine belt drives, applying spring load to keep the belt properly tensioned across the engine accessories.
What are the signs my belt tensioner is failing?
Common signs include belt squeal or chirp, a fluttering or vibrating belt, and a noisy, seized, or worn pulley bearing. Have the cause diagnosed before replacing.
What size is the pulley on this tensioner?
It uses a single flat pulley that measures 70 mm in diameter and 27 mm wide.
Which numbers does this Dayco accessory drive belt tensioner assembly replace?
It cross-references the following numbers: 38419, 49389, 49390, 38418, 999689A, and 999690A.
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.
