I think the U joint is bad?

Hello, I'm Danny.

Here is the information you requested. You will need to remove the driveshaft from the truck to ease in replacement of the u-joint. Here is a tutorial showing how to remove and replace a driveshaft:

https://www.2carpros.com/articles/how-to-remove-a-drive-shaft

I've attached picture steps below on how to remove the driveshaft and replace the u-joints on your truck. Hope this helps and thanks for using 2CarPros.