The Farmer and the donkey

Once upon a time there was a farmer. He was very hardworking. He had an ox, a horse and a donkey who served him. One day the ox told the farmer, "Master, you have a tractor now and you don't need me for ploughing. Please let me go so I can spend my last days in the forest." The farmer let him go. Then the horse said to him: "You don't need me either, master. You have a car now. Please let me go with the ox." The farmer gave him permission to go. Seeing the ox and horse go back to the forest, the donkey too wanted to go. But did not know what to tell the farmer. Suddenly the donkey got an idea.

What plan did the donkey think of? Was it able to go to the forest with the Ox and horse?