Driveline - Clunk or Grunt During Aceleration or Stops

Article No.
96-23-20

11/04/96

DRIVELINE - "CLUNKING" OR "GRUNTING" NOISE DURING ACCELERATION OR STOPPING - 4X4 - 1992-96 F-150/F-250 UNDER 8500 GROSS VEHICLE WEIGHT (GVW) AND 1992-95 F-250/F-350 OVER 8500 GVW

LIGHT TRUCK:
1992-95 F-350
1992-96 F-150, F-250

This TSB article is being republished in its entirety to revise model year coverage and part listing.

ISSUE:
A "clunking" or "grunting" noise from the driveline during acceleration or stopping may be heard on some vehicles. This may be caused by engine torque preventing the slip yoke from sliding smoothly on the transmission output shaft splines. At the same time, rear suspension wrap-up overcomes slip yoke-to-output shaft friction causing sudden driveshaft motion. This can result in a clunk or grunt noise.

ACTION:
Install a revised Slip Yoke (-4841-). The High Phosphate Nickel (HPN) coating on the revised slip yoke splines improves its sliding characteristic. Refer to the following Service Procedure for details.

SERVICE PROCEDURE

1. Perform diagnostic procedure from Section 00-04 of the appropriate year F-150-350 Body/Chassis Service Manual to verify driveline clunk/grunt.

2. If driveline clunk/grunt is verified, remove driveshaft from the vehicle. Refer to the appropriate year F-150-350 Powertrain/Drivetrain Service Manual, Section 05-01, for removal procedure.

3. Remove slip yoke and U-joint from the driveshaft and install the revised Slip Yoke (-4841-) and new U-joint (-4635-). Refer to Slip Yoke Size Determination in this article.

4. Install driveshaft by inserting slip yoke and tightening axle circular flange bolts. Refer to the appropriate year F-150-350 Powertrain/Drivetrain Service Manual, Page 05-00-1 for procedure.

5. Test drive vehicle to confirm repair.

SLIP YOKE SIZE DETERMINATION

Inspect slip yoke removed from the vehicle to determine which slip yoke to use for replacement (either 1350 or 1330 Series). The 1350 Series slip yoke has 30 mm (1-3/16") diameter crossholes and the 1330 Series slip yoke has 27 mm (1-1/16") diameter crossholes. Either measure the crosshole diameter of the slip yoke or try inserting a known series size U-joint into it.

PART NUMBER PART NAME

E4TZ-4841-BB Slip Yoke Assembly (1330 Series)
F5TZ-4841-EB Slip Yoke Assembly (1350 Series)
F2AZ-4635-C Universal Joint (1330 Series)
F5TZ-A635-A Universal Joint (1350 Series)

OTHER APPLICABLE ARTICLES: 87-17-11

SUPERSEDES: 96-14-22

WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage

OPERATION DESCRIPTION TIME

962320A Install Revised Slip Yoke 0.9 Hr.
And Universal Joint
Assembly

DEALER CODING
CONDITION
BASIC PART NO. CODE
4841 56

OASIS CODES: 597997, 702000, 702200, 702300