Hey guys wondering if anybody could help me out, about a month ago I was pulling out of a store and heard a scraping noise for like 2 seconds. Well it's getting more frequent and it stops as soon as I left off the gas. I just crawled under the truck and do not see or feel anything loose. It doesn't effect the drivability either. Just wondering if anybody has dealt with this or know what it could be. Thanks I'm advance.

 

Post details of your truck man (year, miles, trim, etc). I'm suspecting you have a 4x4. If yes, your issue most likely is the vacuum check-valve by the brake fluid reservoir. Lots of info on that for the part number. If you replace it, your issue most likely will disappear. At least it's worth trying since it costs just a few bucks. But you could do a full test if desired; it's explained on that thread. Good luck.

 

Sorry, its a 2018 ext cab sport model xlt with about 6500 miles. I also have a 2.5" bds level and 35x11.5 nitto ridge grapplers. Thanks.

 

It "could" be an IWE wanting to engage due to low vacuum, that checkvalve was a known issue earlier, but Ford has updated it with a "supposedly" better one. Dubious which one you have.
Let's find out if in fact it is an IWE. The next time it happens, throw it into 4Hi, if it is an IWE, the scraping should stop, just like when you back off the throttle.
When you back off the throttle, vacuum increases, and pulls the IWE into the disengaged position. When loosing vacuum, acceleration, there isn't enough vacuum to hold the IWE out, therefore wanting to halfazz engage, and causing that scrapping/grinding/stone in the disc brake sound. If you could provide a video, that would be helpful.

Normally, 2Hi, the IWE is provided with vacuum keeping them disengaged.
When you switch to 4Hi, a solenoid clicks over, venting vacuum from the system, and allowing the hubs/IWE to engage.
If that checkvalve is bad, it's allowing the system to vent off vacuum and the IWE will try pulling in.

 

Brought it into the dealer due to its still being in warranty and that was exactly what it was, the check valve on the vacuum system. Thanks a lot guys for the info made explaining to the dealer much easier. Thanks again.

 

Glad to hear that, hopefully you won't have anymore trouble.
My '17, IIRC, had less than 500 miles on it when I replaced that valve. My '12, with 58K on it, never had a problem for the 5 years I had it. "4X4 F150's are like a box of chocolates,,,,,,,,,,,,"

 

Thanks much for these posts. We are on a 600 mi trip in a 2018 F150 Platinum 3.5 EB 4x4 and the exact metal-on-metal scraping/grinding sound occurred (about 2 sec duration also). "What the *&%$#" was that?" It occurred on acceleration - but only around town. We thought is sounded like front brake pad or caliper dragging on rotor or some sort of friction plate dragging within the transmission. Once on the Interstate, no sound upon accelerating.
'Haven't tried to drop it into 4WD yet but glad to know that is an option as we still have 500 mi go. Called service manager at home dealer who suggested vacuum check-valve - will take truck in tomorrow to confirm.
Will report outcome here.

Of note, Check engine light had gone on earlier in the trip (before this symptom). Also, truck had thrown a "Check fuel filler (?)" warning message about 2 weeks earlier. Dealer tech diagnosed this as an issue with pulling gas from the tank (vacuum?). Replaced some (?) part which didn't clear the code...so they surmised the vacuum had pulled so hard as to damage the fuel tank...next service appt is to (wait for it) replace fuel tank.

Perhaps there is a holistic vacuum issue... very curious to solve this mystery!

 

SSM 47360 - 2013-2018 F-150, 2017-2018 Expedition/Navigator - Intermittent Grinding Noise From Integrated Wheel Ends (IWE) While Driving In Two Wheel Drive (2WD)

Some 2013-2018 F-150 and 2017-2018 Expedition/Navigator vehicles may exhibit an intermittent grinding noise coming from the right or left IWE area in 2WD mode. This may be caused by an intermittent leak in the check valve. Before completing any normal diagnosis suspect that the check valve is the root cause of the issue. An updated check valve (7A788) is now available that resolves this concern.

 

Supposedly not even my June-2018 built truck has the 7A788 valve, so I'm going to buy it next time I order something (along with the shifter LED bulb so it lights up at night). Any grinding can damage the IWEs, so better act proactively before any grinding happens, especially when the part is less than 10 bucks.

 

Cheap insurance for sure, that's a good idea. Let's all hope the "new and improved" version, actually is improved.