2000 E-150 Conversion Van 4.6 front end noise
 

Hello everyone. I have a 2000 E-150 with 122,000 miles. After driving the van for like 30 minutes I start hearing and feeling a clunking noise I believe from the front or could be centered, but it is so hard to tell. The faster I go the faster the noice clunks (like a rotating part). It also happens while putting the breaks on. I have no idea what this could be. I took it to an automotive shop and even had a mechanic ride with me and he heard it. He put it up on the lift and still could not pinpoint what was wrong. I would appreciate any help. Thanks

Did he check the u-joints in the driveline?