Hi all, I'm hoping someone can help me pinpoint a knocking noise coming from my front end. It definitely has something to do with the drive line. Basically at low speed I hear a knock, knock,knock rotation sound that is coming from the centre of the front end. I especially hear it at very low speed and it turns more into a whirring sound as I speed up. The sound appears no matter if it's in reverse, forward, while the engine is running or if it's off and rolling in neutral, turning or going straight. I can almost feel the sound in the pedal if that makes sense.
If I put my truck in 4x4 it somewhat changes from a knocking to almost a rubbing sound or feel.

My truck is a 01 Supercrew Lariat, 4x4 with the 5.4 with about 95000 km on it.

Thanks in advance for the help.

 

sounds like the transfer might have problems or the front differential. Jack up the front end and turn both front tires while they are in the air and see if it happens. By engaging the 4x4 system you are changing the torque on the transfer and front differential as well as axles thus changing any noises that may be coming from there.