I have a 07 F150 Crew 4x4 short bed. The last time I drove it was going 25 mph down street then heard loud bang then a ginding noise from under hood. Just before I reached a full stop heard another bang and the noise went away. Then going about 45mph same thing happened but I put in 4 wheel hi and noise stopped right away. Drove home in 4 hi but on the way home put it back in 2 hi and after a couple of miles same thing happened, I put it in 4 hi and problem stopped right away. Anyone have an idea what could be wrong? Truck is at dealer and they don't know. Thanks

 

I don't know either, but it sounds every expensive. Good thing you are under warranty!

I hope Ford and your dealer treat you right.

 

Search for the TSB on the IWE solenoid, its a known issue. I had it on my 06.

 

When this happens, does your 4x4 dash light go on and off? I'm having a similar problem when my 4x4 light intermittantly goes on and off.
When my light goes on, I get a clunk like the 4wd is trying to engage, then it grinds until I hear another clunk...light turns off and the grinding stops.
A possible giveaway is click, like a relay or solenoid activating someplace on the passenger side of the truck every time the light and the clunk happen.
Yo SoxFan...can you give a bit more insight into the problem and how we might take care of it?

As always, any help is greatly appreciated....

 

I don't know if my 4x4 light flickered but it was the iwe solenoid behind the battery. Check your hoses from the solenoid to each wheel, sometimes they get worn and leak and that causes the 4x4 to try and engage. The dealer replaced the solenoid and the truck has been fine. Thanks for everyones help.