Congrats on getting your truck paid for. Now, take most of that truck payment and put it into savings for when you have to replace that truck. I did that years ago when I was working after I had paid off my car, I kept taking the car payment out and putting it into savings. When I had to replace the vehicle I had enough cash to pay the difference on the trade in and didn't have car payments. Just kept up with that car payment into savings and people at work wondered how I couldn't have a car payment when I traded vehicles. You have been making it without the additional cash for now and if you don't save it, it will fritter away here and there and you won't have a lot to show for it. As one of the ladies suggested, you could also use part of it to pay additional on your house, thereby saving you a bunch of interest and it would probably help your credit that much more as well.
Anyway glad for you and hope the truck continues to run for a long time with no problems, with the mileage you have accumulated you probably can get two more years on the warranty if it goes according to mileage.