Get a truck manual from your local auto parts store and go to town.
1. Can o worms. Will need to know where you live or weather conditions truck will see.
2. Stock recommended. (Will be in the above manual)
3. Check/replace all fluids is a GREAT IDEA.
Pics of your 1st gen required before we can offer any more advise!
![Cheesy :D](https://board.marlincrawler.com/Smileys/marlin/grin.gif)