I need some answers on tire sizes for stock suspension and stock wheel setup. I want to run a 255/45 tire. Let me know if this is possible and what u guys think.

 

You should run 255 with a 40 sidewall.

 

On the factory 8" rims the widest you can go is a 245/40 or a 245/45, a 255/40 needs a 8.5" rim according to every tire manufacturer for every tire model I've ever seen. A 255/45 is 26" tall, over a 3% change in diameter.