weird turbo noise

[powerstroke welding rig]

I just finished cleaning my turbo and the turbo spools up great and sounds great. Besides an exhaust leak that I fixed everything seemed okay. Tonight I picked up my camper and brought it home. Its a 30 foot tow behind. I drove about 5 miles with it. A couple of times when my turbo spooled up I would take my foot off the pedal suddenly and it sounded like my turbo was kinda making like a groaning sound.

I can compare the noise to a stuck open Blow off valve. On my old Mitsubishi eclipse I had the Blow off valve stay stuck open. If you know what that sounds like then you will have some idea what I am hearing.

After supper I unhooked the trailer and went to the store. I was trying to get the truck to make the noise again but no matter what I did I couldn't make it. I don't have any gauges yet so I cant give you any boost numbers. Sorry

If anyone has any ideas please let me know. Thank you very much.