Owners of some 2007-08 Ford and Lincoln models with 4.6-liter and 5.4-liter engines may complain of a high-pitched hoot or whistle from the accessory drive belt system at idle.

According to Ford, the noise is most obvious on cold start-up in temperatures below 40°F, usually stops after about 10 minutes of driving and is due to grooves forming in the nylon belt idler pulley.

Installing a new-design, more robust idler pulley, part No. 6L3Z-6C348-A, should eliminate the issue in short order.

Vehicles that are prone to the noise and can benefit from the updated idler pulley are 2007-08 F-150s and Mustangs with 4.6-liter and 5.4-liter engines; 2007-08 Lincoln Mark LTs/Navigators and Ford Expeditions with 5.4-liter engines; and 2007-08 Ford Explorer and Explorer Sport Trac and Mercury Mountaineers with 4.6-liter engines.

"Factory Fixes" is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected] .

Do you have an opinion about this story? Do you have some thoughts you'd like to share with our readers? Tire Business would love to hear from you. Email your letter to Editor Don Detore at [email protected] .

Please enter a valid email address.

Please enter your email address.

Please select at least one newsletter to subscribe.

Staying current is easy with Tire Business delivered straight to your inbox.

Tire Business is an award-winning publication dedicated to providing the latest news, data and insights into the tire and automotive service industries.