There are loads of audiobooks on you tube the only issue being that it will use a fair bit of data as its streaming as video, I have a 30gb contract a pair of good quality bluetooth headphones I never listen to the radio in the truck, the BBC radio player is excellent with a seemingly endless amount of content there is an app called tunein which is excellent with thosands of stations from around the world with every genre imaginable.
I personally like you tube for books as you can save a book to your playlist and pick it up where you left off giving you the ability to listen to multiple books or music at any given time the 3 network seems to work for me, when I rarely have to drive the car something a find a necessary chore the wife listens to Capital Radio broadcast from Cardiff mindless beyond all belief.
A few quid £150 for the cans and a big data sim and a smartphone and you never have to chew your fist ever again.