dvdrntn

Help please. In my 2.0 diesel Cmax 56 plate (58000 miles) i have started to get a whirring sound when i reach more than 30mph.
It is not their at idle and revving whilst stationary.
When i come off power at speed it sounds like when you are descending on an airliner, the noise is present whilst normal driving as well but more prominent when freewheeling.
I first experienced this 3 weeks ago then it stopped doing it(it then included a bit of juddering at 70-75mph(only a couple of days) I then had it fully serviced and 2 new front tyres fitted(did nt mention issues to garage as it had gone away and didnt want to give them license to print money)-now regretting it) -, i have done 600 miles since service and it was nt obvious straight after svc. Should i involve the garage and should they have noticed the fault which i think was intermittent before and after service. Have i got anything to gain by saying it happened only after service. No electrical indications. Thank you for your time.