TSB 04-15-4 RATTLE NOISE FROM PRIMARY CHAIN DRIVE AREA 2000-3000 RPM - 4.0L SOHC ENGINE
FORD: 1999-2002 Explorer, Mountaineer
2001-2002 Explorer Sport Trac, Explorer Sport, Ranger
This article supersedes TSB 02-08-01 to update part numbers and add a labor operation for vehicles with auxiliary air conditioning.
ISSUE:
Some vehicles equipped with the 4.0 SOHC (single over-head cam) engine may exhibit a primary timing chain rattle noise. The noise is heard during hot and cold engine operation (but mainly heard on cold engines) under acceleration, typically at 2400-2500 RPM. To verify concern, accelerate in 2nd gear between 2000 and 3000 RPM and listen for rattle noise that sounds similar to spark knock. This may be caused by the primary timing chain tensioner system.
ACTION:
Replace the Primary Timing Chain Tensioner, Chain Guide, Jackshaft and Crankshaft Sprockets with a Primary Timing Chain Tensioner Kit. The Kit includes an improved Primary Chain Tensioner, as well as updated Primary Chain Guide, Primary Jackshaft, and Crankshaft Sprockets. Required fasteners, Primary Timing Chain, and Front Cover Gaskets are also included. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
Verify the condition. Obtain the correct Primary Timing Chain Tensioner Kit and follow the instruction sheet supplied with the Kit.
Use Kit 2U3Z-6D256-CA (balance shaft engines) for:
1999-2001 4X4 Explorer/Mountaineer
2001-2002 4X4 Sport/Sport Trac
ALL 2002 Explorer/Mountaineer, except engine codes 2G-960-AA and 2G-964-AA.
Use Kit P/N 2U3Z-6D256-DA (non balance shaft engines) for:
1999-2001 4X2 Explorer/Mountaineer
2001-2002 4X2 Sport/Sport Trac
2002 MY Explorer/Mountaineer with engine codes 2G-960-AA and 2G-964-AA
ALL 2001-2002 Ranger