When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
My first thought is that your fan clutch may be the source of the sound. I had a similar experience around 250K, replaced the fan clutch and solved it. If it helps, I think I recall the sound was much more pronounced on hot days.
--
Rick
I purchased a new fan blade about a year ago. Noticed the sound started a few months ago. Just because it is new, doesn't make it good. I'm pretty sure you are right.
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
