Pulley Runout/Uneven Rib Height Causing Accessory Drive Belt Squeal (Export Only)

This bulletin is being revised to include an additional procedure to ensure there are no further belt squeal noise complaints. Please discard Bulletin No. H06-06-03, Issue 1.

Some HFV6 vehicles may exhibit an accessory drive belt squeal noise that may be present when engine is cold and generally within the first few minutes of operation until engine is warmed up*.

* Do not mistake this noise with a characteristic "start-up belt chirp" noise that may occur on some HFV6 M/T vehicles -- present only at start up for 2-3 seconds.

Investigation of accessory drive belt squeal cases has defined that power steering pump pulley (HSPO P/N 92066499) lateral runout and pulley rib height may be out of specification.

Power steering pump pulleys with certified correct lateral runout were introduced at:

Power steering pump pulleys with certified correct rib height were introduced at:

After verifying that the vehicle has the condition described above, perform the following procedure.

Important: Before removing the belt, note the direction of the belt. Mark the belt with an arrow towards the front of the vehicle and place it back in the same direction when the procedure is completed.

1. Confirm that the accessory drive belt noise is coming from the passenger side of the engine compartment.

Check belt rib runout in area indicated by arrow




2. Remove the accessory drive belt and spin the P/S pulley and measure the lateral runout. Allowable runout on the belt ribs of the power steering pulley is 0-0.4 mm. Do NOT check the runout via the outer flanges as these flanges are not as accurate as the inner belt ribs. Use of a dial indicator is recommended for this check to ensure accuracy.

If outside of specification, replace the P/S pump pulley.




3. Some pulleys have been identified as having "uneven rib form" as per the illustration above. This can be checked by placing a straight edge across the ribs to confirm uniformity. Any pulley with uneven rib form should be replaced.
4. Reinstall the original drive belt. Install as per the marking as noted at start of this procedure. Test to confirm that the noise is eliminated.

Additional Checks

Should any noise complaint persist after a pulley replacement, the following checks should be performed.

Important: A laser-type belt alignment checking tool is advantageous for conducting quick and accurate alignment of the accessory drive belt system.

1. Check the P/S pulley to P/S pump shaft offset (refer to the illustration above). If not to specification, align the pulley back to specification (0-0.3 mm underflush).
2. Check the belt alignment to ensure that misalignment of the belt or pulleys is not the cause.