What a challenge.... Odd truck problem

I’ve got a 2006 f150 4x4 v8

I get a grinding noise (I think it is coming from the front left of the truck) that lasts only a little while and only comes out after a cold night (so I only get the noise in the morning after the truck has sat overnight)

The issue details:

  1. The grinding noise is constant and the truck has to be moving for it to make the noise
  2. The truck will only make the noise while driving forward, it disappears when I drive in reverse
  3. The truck has to sit overnight and it has to be cold (below freezing)
  4. I only get the noise if I go in reverse BEFORE I drive forward after the truck sat all night
  5. Will not make the noise while in 4x4
  6. It has been doing this for about 2 months

What I tried:

  1. Replaced both front wheel hubs
  2. Replaced 4x4 vacuum and checked the lines for pressure
  3. Front brake pads and checked calipers
  4. While the truck was making the noise unplugged the 4x4 vacuum - still made the noise

Any help would be greatly appreciated and would also help with my blood pressure!

When you start up in the morning, I’m guessing you back out of a driveway or parking spot, turn hard while in reverse, then put in a forward gear and that is when the noise starts. Are there CV joints in the front end and were they replaced along with the hubs?

First, check the belts. They make strange noises just like you described. They do it at times that would make you believe it’s coming from somewhere else.

I suspect your front left Wheel Hub…As in 4WD wheel hub…Do you have Auto hubs on this truck? If so they are a KNOWN ISSUE…my auto hubs on my Exploder are STILL causing be greif…Sounds as if the hub has not fully disengaged and is “in between” when this occurs you will hear a grinding sound…I wont go into all the details on the why’s of it all…

You can gather the details of the Auto Hubs at this Ford Explorer site

In the site you can read ALL ABOUT the headaches we go thru with the Auto Hubs…the fix is manual hubs…which I am still going to do to mine…

But I would look into your front left hub…sounds like textbook Auto-Hub syndrome to me

YIKES…I just re-read your post and see that you replaced the Hubs already…HMMMM…I hate to say it but I think the issue STILL resides there or somewhere in the 4wd system in regard to the front left wheel and hub…perhaps you can learn more on the website I gave you… I HATE AUTO HUBS

Blackbird

SOLVED! (for now)

Part needed was… 2004-2011 Ford F-150 F 150 4x4 Hub Lock Actuator IWE

What had happened was water was getting sucked into the system by the hub vacuum, which is brilliantly located by the firewall of the truck - directly UNDER WHERE ALL THE WATER RUNS OFF THE WINDSHEILD! Really! That’s where you are going to put a vacuum system!

So over time water had got into the Actuator and displaced it enough that the shaft wouldn’t go into the hub straight. Hence the horrible teeth grinding noise. Also explains when on cold days it was worse because the water in the actuator would freeze and compound the problem, and when I would back up it would reset it self - and when i would then drive forward it would try to engage because of the displacement of the actuator!

StupidTruck!