John and Dai hadn't seen each other in years and met by chance and they discussed what they were both doing now. John was a lorry driver and Dai a Farmer.
On his next journey John decided to take a detour and surprise Dai. He got out of the lorry cab and heard smooching sounds coming out of one of the sheds, so decides to investigate. He's shocked to see Dai stark naked kissing the headlights of a farm machine. " Dai, what are you doing mun ?" he splutters Red faced Dai turns to him and says, " It's like this bud, I'm having trouble in the bedroom department ... and the Doc says I've got to do more to a tractor ..."