Odd noise after inverter coolant service...

Hi all. Hoping someone could help with this. I brought my 07 Touring, 95,000 in for regular service, plus inverter coolant change, serpentine belt replacement, clean and adjust rear brakes, new oem tires and an alignment. They also performed the steering column recall. 12 Volt was changed three months ago... Car has no problems and is the best vehicle I have ever owned...

The next day, while pulling into my driveway, I heard a gurgling sound, and my car dumped about three to four ounces of radiator coolant. I returned to the dealer, and they said that they found a loose clamp on one of the coolant hoses.

However, since all this service, I now hear an intermittent whoop, whoop, whoop sound when I come to a stop. It is random, audible, and last anywhere from 2 to 10 seconds. It doesn't even happen every day... Has anyone ran into this before? Any ideas would be greatly appreciated...

I was thinking maybe the serpentine belt is too tight, or the pully is making the noise? Did they do something to my inverter pump when changing the fluid???

Thank you in advance!