Hey guys, I just signed up for this forum today. I have a 2003 F150 Stepside Lariat 4X4 with the 4.6L. I got it at about 38,000km and it has about 50k on it now. Everything is great on the truck, and I can tell that it was very gently used before I got it. My question is regarding the 4X4 system. It's got the electronic select, and it goes into 4WD just fine. When it's in 4X4 though I can hear a distinct humming noise coming from the front of the vehicle, sounding similar to the engine but quieter and a different pitch. This only really happens when I am accelerating, and when I'm coasting it goes away. It kind of drones with the sound of the engine. Is this normal? Are there supposed to be some other sounds happening when 4X4 is engaged? Thanks a lot, and it's nice to be a part of the F150 online crew.

 

Most likey that's just the whine associated with the transfer case. Nothing to worry about unless it gets unusually loud, but mine does that too, and just about every 4x4 I've ever had does the same thing.

Welcome to the site!--DIY