Under normal use, the serpentine drive belt should be inspected at around 45,000 miles or after 3-4 years of service. If not replaced at this time, the belt should be checked each additional year or 15,000 miles. Under severe and off-road conditions inspect the belt annually. When diagnosing serpentine drive belts, small cracks that run across ribbed surface of belt from rib to rib are considered normal. These are not a reason to replace the belt. However, cracks running lengthwise along a rib (not across) are not normal. Any belt with cracks running lengthwise along a rib should be replaced. Also replace the belt if it has excessive wear, frayed cords or severe glazing.
Warning: Spring tensioners should not be disassembled because of high spring tension. The tensioner unit is serviced as an assembly.
3.0L V6 diesel engine:
3.0 Engine belt routing and tensioner release location
3.7L / 4.7 V8 engine:
3.7L / 4.7 engine belt routing and tensioner release location
5.7L / 6.1 V8 engine:
5.7L / 6.1 engine belt routing and tensioner release location
NOTE: If anything differs between the pictures shown above and the Belt Routing Label (located in the engine compartment), use the schematic on the Routing Label.
CAUTION: DO NOT LET TENSIONER ARM SNAP BACK TO THE FREEARM POSITION, SEVERE DAMAGE MAY OCCUR TO THE TENSIONER. SLOWLY RELAX THE TENSION BACK TO THE STOP POSITION.
1. Disconnect negative battery cable from battery.
On 3.0L engines, use a 12 point, 17mm socket and a long handle ratchet (3/8″ drive) to rotate the accessory drive belt tensioner (5) counterclockwise until it contacts its stop. Remove accessory drive belt. Slowly rotate the belt tensioner back into its freearm position.
On 3.7L and 4.7L engines, use a 15mm socket wrench to rotate belt tensioner clockwise until it contacts its stop. Remove belt and slowly rotate the tensioner into the freearm stop position.
On 5.7L and 6.1L engines, remove the air intake tube between intake manifold and air filter assembly. Using a 3/8″ square drive ratchet end, release the belt tension by rotating the tensioner clockwise. Rotate the tensioner until belt can be removed from pulleys. Remove belt and gently release tensioner.
3.0L engines – Position accessory drive belt around all pulleys except the idler pulley. Rotate the belt tensioner counterclockwise until it contacts its stop position. Route the accessory drive belt around the idler (8) and slowly let the belt tensioner rotate into the belt. Make sure the belt is seated onto all pulleys. .
3.7L and 4.7L engines – Route the belt around all pulleys except the idler pulley. Rotate the tensioner arm clockwise until it contacts its stop position. Route the belt around the idler and slowly let the tensioner rotate into the belt. Make sure the belt is seated onto all pulleys. Inspect the entire belt path to make sure belt is properly routed and all V-grooves make proper contact with pulleys.
5.7L and 6.1L engines – Position the drive belt over all pulleys except for the water pump pulley (7). Rotate tensioner clockwise and slip the belt over the water pump pulley. Gently release tensioner. Make sure the belt is seated onto all pulleys. Inspect the entire belt path to make sure belt is properly routed and all V-grooves make proper contact with pulleys. Install the air intake tube between intake manifold and air filter assembly.
Reconnect negative battery cable to battery.
On 3.7L and 4.7L engines, the tensioner is equipped with an indexing tang on back of tensioner and an indexing stop on the tensioner housing. If a new belt is being installed, tang must be within approximately 24 mm (.94 inches) of indexing stop. Belt is considered new if it has been used 15 minutes or less.
WK Serpentine belts
3.7L / 4.7L
3.7L / 4.7L
(Prices listed are for reference purposes only and may vary by dealer. MSRP prices are current as of March 2012. Parts are not available from this web site.)