Fulltext TSBs

Technical Service Bulletins

TSB
03-21-19
  • ENGINE – 7.3L DI – VIBRATION AT 2600-3000 RPM – VEHICLES WITH 4X4
  • NOISEVIBRATION – MOANING/VIBRATION AT 2600-3000 RPM – VEHICLES WITH 7.3L DI AND 4X4
Publication Date: October 6, 2003

FORD:
1996-1997 F-250, F-350

Article 97-1-13 is being republished in its entirety as part of a consolidated 7.3L diagnostic aid booklet.

ISSUE:

An engine vibration and/or “moaning” noise at 2600-3000 RPM may occur on some vehicles. This may be caused by an imbalance within the engine, flywheel and clutch.

ACTION:

Add a known mass value in the best location on the clutch to reduce the vibration and/or “moan.” Refer to the following Service Procedure for details.

SERVICE PROCEDURE

NOTE:THE VIBRATION CONCERN CAN ALSO BE FELT FROM THE SEAT, FLOOR AND STEERING WHEEL ON NEUTRAL RUN-UP OR WHILE DRIVING IN GEAR IN THE SAME RPM RANGE.

  1. While verifying the concern, notice the vibration difference coming from the clutch pedal and manual transmission shift lever at 2000-2500 RPM versus 2600-3000 RPM.
  2. Remove the four (4) bolts attaching the dust cover to the engine and transmission bell housing and remove the cover.

    NOTE:USE A SOCKET AND BREAKER BAR WRENCH TO ROTATE THE ENGINE AT THE FRONT PULLEY FOR LABELING AND LOCATING THE PROPER BOLT FOR BALANCING. REMOVE THE WRENCH BEFORE STARTING THE ENGINE TO EVALUATE THE VIBRATION/”MOAN.”

  3. Number the eight (8) clutch pressure plate-to-flywheel attaching bolts (5/16″-18×0.75″, Grade 8), 1 through 8 with paint marker (Figure 1). There are two (2) bolts at each corner of the clutch.
  4. Adding known mass at one (1) or two (2) of these bolts will reduce or eliminate the vibration concern. Start with known mass consisting of one (1) standard Grade 8, 5/16″-18×1″ bolt with a 1/2″ head, three (3) standard 5/16″ flat washers, and one (1) standard 5/16″ lock washer. Use the following method for finding the best location for adding this known mass to correct the vibration:
    1. Remove bolt Number 1 (Figure 1) and replace the known mass bolt assembly. Torque the known mass bolt to 30-40 N-m (22-30 lb-ft). Start the vehicle and rate the vibration at 2600-3000 RPM.
      • If the vibration/”moan” is eliminated or improved to an acceptable level, leave the known mass in place, install the dust cover and return the vehicle to the customer
      • If not proceed to Step 4b.
    2. If the concern is worse or is near the same, replace bolt Number 1 with the original bolt and install the known mass bolt assembly at Number 3 (Figure 1). Torque the known mass bolt to 30-40 N-m (22-30 lb-ft). Start the vehicle and rate the vibration at 2600-3000 RPM.
      • If the vibration/”moan” is eliminated or improved to an acceptable level, leave the known mass in place, install the dust cover and return the vehicle to the customer
      • If not proceed to Step 4c.
    3. If the concern is worse or is near the same, replace bolt Number 3 with the original bolt and install the known mass bolt assembly at Number 5 (Figure 1). Torque the known mass bolt to 30-40 N-m (22-30 lb-ft). Start the vehicle and rate the vibration at 2600-3000 RPM.
      • If the vibration/”moan” is eliminated or improved to an acceptable level, leave the known mass in place, install the dust cover and return the vehicle to the customer
      • If not proceed to Step 4d.
    4. If the concern is worse or is near the same, replace bolt Number 5 with the original bolt and install the known mass bolt assembly at Number 7 (Figure 1). Torque the known mass bolt to 30-40 N-m (22-30 lb-ft). Start the vehicle and rate the vibration at 2600-3000 RPM.
      • If the vibration/”moan” is eliminated or improved to an acceptable level, leave the known mass in place, install the dust cover and return the vehicle to the customer
      • If not proceed to Step 4e.
    5. If the concern is improved at any of these locations but not eliminated, further improvement may be obtained by transferring the known mass bolt assembly to the adjoining attaching hole or splitting the mass between adjoining holes (e.g., location Number 2 for Number 1 or Number 6 for Number 5, and so on).

      NOTE:PAY ATTENTION TO THE LENGTH OF THE KNOWN MASS ATTACHING 5/16″ BOLT USED SO THAT IT DOES NOT EXTEND BEYOND THE WIDTH OF THE SECONDARY FLYWHEEL WHERE IT COULD COME IN CONTACT WITH THE PRIMARY PORTION OF THE DUAL MASS FLYWHEEL WHEN TIGHTENED.


PART NUMBERPART NAME
(Obtain Locally)Bolt – 5/16″-18×1″ (Grade 8)
(Obtain Locally)Flat washer – 5/16″ (3 Req’d.)
(Obtain Locally)Lock washer – 5/16″

OTHER APPLICABLE ARTICLES:

NONE

SUPERSEDES:

97-1-13

WARRANTY STATUS:

Information Only




Figure 1 – Article 03-21-19


NOTE: The information in Technical Service Bulletins is intended for use by trained, professional technicians with the knowledge, tools, and equipment to do the job properly and safely. It informs these technicians of conditions that may occur on some vehicles, or provides information that could assist in proper vehicle service. The procedures should not be performed by “do-it-yourselfers”. Do not assume that a condition described affects your car or truck. Contact a Ford, Lincoln, or Mercury dealership to determine whether the Bulletin applies to your vehicle.

Copyright 2003 Ford Motor Company