2017 F150 3.5 ecoboost - I had the grinding noise and issues with 4WD, dealer replaced the items listed below under warranty about a year ago. There has been a few times throughout the winter that the 4WD has had issues, not engaging properly, and traction issues, but no noise like before…until today. It’s been a 5 or 6 weeks since I’ve used 4WD, and randomly pulling out of my driveway today (in 2WD) I heard a bit of that grinding noise for a few seconds.

1st question: did the dealer replace all of the necessary parts?
2nd: any idea if there’s something else that would cause issues?

Thanks, appreciate any info you can provide.

1 valve assembly (7L1Z 9H465 B)
1 tube assembly (FL3Z 3A788 B)
2 actuator assembly (HL1Z 3C247 A)
2 hub assembly (HUB 393)

tech’s description: inspected and verified customer concern, pulled vacuum hose off of both IWE's when running in 4H and there was still vacuum being applied to both front WE's, scanned for codes and found code c1979, performed pinpoint test C for the code and test directed to install a new IWE control solenoid, installed new solenoid and tested 4WD and found both front IWE's to only be partially engaging, performed TSB 22-2219 and upon removal of both of the front IWE's found that they have ground down the teeth on the back of both front wheel bearings, removed and replaced both front wheel bearings, both front IWE's and vacuum check valve and re tested vehicle, 4WD is now working properly.

 

If you don't get any replies soon it would be good to re-post this in the "2015 - 2020 Ford F150' forum subsection as well.

 

Ok, I’ll give that a try ! Thanks, I appreciate that!