need some tips and tricks

i hope im doing this rite and asking the rite way, but what can i do to my 1994 dodge ram 1500 4x4, it has a 318 and has 150,000 miles and still running good but could be better i need a few tricks and tips to get it running like a top... i use lucas oils through out the whole truck and it helps but i know i need sum new things but dont have alot of money... but im getting my spending limit up so i can do more things to it..... so if you wouldnt mind could you throw some help my way?... o by the way i have given it a tune up...