Hey everyone, first-time poster here, so apologies if this has been covered before.
About a year ago, my truck started making a subtle groaning/growling noise near the pedals when braking below 30 MPH, and I could feel the vibration through the floor.
Over the summer, it went away, so I didn’t think much of it. But now that winter is back, the noise is louder and lasts longer. It starts when braking around 30 MPH and sometimes sticks around while speeding back up until about 10-15 MPH.
Took it to two different mechanics, and both said it was the front differential. So I dropped $3,000 on a full rebuild… and the noise is still there—worse than before.
I’d bet on the IWEs (Integrated Wheel Ends). You’d think Ford would’ve figured out by now that vacuum hubs aren’t worth a damn, but here we are.
I had to replace one on my 2016. The other side still acts up in very cold weather, but I can usually get it to shut up by quickly flipping into 4H and back to 2WD.
@Peyton
Tried that, and it did improve the symptoms! After driving around, I crawled under to check the lines and found a torn axle boot with grease everywhere… The dealership just had that apart when they did the front diff last week.
Zadie said:
Does it happen when turning? IWEs tend to make a ratcheting noise when they go bad, especially when accelerating and turning.
Nope, happens when going straight.
Could still be bad IWEs. If it were wheel bearings, the noise would just keep getting worse, not come and go.
Does your truck have a 4WD Auto mode on the dial? If so, there’s a cheap fix where you cap off the vacuum lines going to the IWEs. Ford actually has a TSB (Technical Service Bulletin) on this—they cap off the vacuum and reprogram the transfer case module.
Have a mechanic check if the IWEs hold vacuum and disengage properly.
If you want to test yourself, jack up the front end while the truck is running and make sure the wheels spin freely, but not the front axles, when in 2WD.
