mnhuntr

I have a 2012 4x4 ecoboost. For the past couple of winters, as soon as the temps get cooler, I get a growling coming from the front end. It only does it for the first few miles (usually disappears after up to 8 miles, sometimes sooner). When it is doing it, it isn't constant. Usually for a few seconds (3-15 seconds) and then will quit for a couple seconds and then starts again. When temps are in upper 70's and above, I don't hear it all. When it does do it, I have tried shifting into 4Hi to see if it is something vacuum related to the 4wheel drive system but it usually continues. I took it to dealer last spring and they said they could only hear aggressive tires (Goodyear Duratracs). Well, I put new tires on recently and now dealer has admitted to hearing it. They have tried new vacuum actuators, a new driveshaft, along with tearing into the front end to check bearings. So far nothing has cured it. If you drive it far enough for it to quit and then park for an hour, it will do it again. They said it doesn't do it on the rack, only when under load. Doesn't do it idling. Dealer has had it now for almost 2 weeks trying different things to no avail. Any suggestions?

akeco

I'm curious as well as when my truck is cold I hear like a pump sound almost running for a couple seconds then it quits... Usually when I start the truck. And when I stop to get the mail on the way home and put it in park too. Truck is good and hot then tho...

boostdriver

Like this?

Locopopo871

subscribed.....mine did it the other day

Coastline

The only growling sound I ever hear is sitting next to me.

mnhuntr

Dealer got it fixed. Ended up being the vacuum actuator on the hub not completely sealing. When they first replaced them and it still did it, they figured it must be something different. Turns out one of the new ones installed was bad. No more growling.