Hi! As the title suggests I'm new to this forum and I will be looking for all sorts of help. I currently own a 1999 Chevrolet Silverado. I love my truck! I have had many "friends" do various work on it over the past few years and now I would like to start learning how to do things on my own. Today I pulled out the EGR valve to clean it because the truck has been having some "stuttering" problems over the past month. I replaced the plugs and wires and that didn't fix the problem, so someone suggested cleaning the EGR valve as my next step. My first question to this forum is, how do I determine whether I have a 4.8L or a 5.3L engine? I know it is an 8 cylinder, but everytime I go to buy or price parts they always ask me whether it is 4.8 or 5.3. How much of a difference is there? And will this difference effect the parts that I buy? I look forward to your help and I can't wait to put some more hours in under the hood.