Mayo was the voice of Drivetime for eight years but announced he would be leaving to focus on writing after just a few months co-presenting with Whiley in what proved to be a divisive change of format.
Cox became the favourite to become the new presenter of Drivetime following the announcement of Mayo’s departure last week.
She has now been confirmed as the DJ’s replacement, and said she is “proud” to take over the slot, which will run from 5pm-7pm. She had previously been heavily tipped to take over presenting duties on Chris Evans’ Breakfast Show, but lost out to Zoe Ball.
Cox said of being handed the time slot: “I’ve been proud to be part of the Radio 2 family for a few years now and the opportunity to present such a big show as Drivetime - playing fantastic music and hopefully making people smile as they cook tea or head home after a day’s graft - is the icing on what is already a very brilliant cake.
“I’m beyond chuffed to be given this role and to directly quote my mum on hearing the good news, it is indeed ‘fandabbyruddydozy’.”
The BBC have not yet announced when Cox will begin presenting Drivetime.
Cox has experience on the station, most recently as a stand-in presenter on the Breakfast Show. She joined the BBC in 1999 and worked on Radio 1’s Breakfast Show.
There was consternation from some audience members when the Drivetime show was reformatted.
Mayo defended Whiley online saying: “I’ve loved working with the exceptional Jo Whiley and when the show was ‘reconfigured’ she was my first and only choice.”
He added in another Twitter post: “Support for a show is one thing, assaulting the dignity of a warm-hearted and loyal friend is another.”
Whiley will not remain on the show and will be launching a new show from 7-9pm, Monday to Thursday.
Cox is understood to be the sole presenter of Drivetime.
Lewis Carnie, the head of Radio 2, said: “Sara is hugely popular with the Radio 2 audience and I have every confidence that she’ll make the new Drivetime show her very own.”
In another shake-up to the radio schedule, Trevor Nelson will be moved from his 8-10pm Saturday night slot, to present from 10pm to midnight from Monday to Thursday.
He said: “To present eight hours a week of the music I love on BBC Radio 2 is a dream come true for me.”
Nelson will also continue to present on BBC Radio 1 Xtra.