Hey everyone I was wondering what were some of the big changes that GM performed on the Sierra/Silverado over the different model years.

I am mainly concerned about the 5.3L engine from years 1999-2003. I have heard something about the 6.0L cam in one of the later models but I am not sure when and if this mod was performed.

So if anyone has any info on this subject I would appreciate it since I am trying to figure out what changes effected my 2003 5.3L Sierra.

Also I finally broke in my new truck! Its got about 2300 miles now and drives amazing. Before I had to really push it to break the tires loose from a dead stop but now its a whole other world. I think I really broke it in right! Now I can stab the gas from a dead stop even with traction control on and it really spins the tires, until the lockind diff does its job. Surprisingly the traction control rarely intrudes unless I am in wet conditions. With the traction control off the truck just sits there spinning the tires with the rear end hopping up and down! What an engine they put in this truck!

thanks for any info you guys send me!

Glenn

 

I know from 99 to 00 they changed cams in the entire ls1 line up and uped horses by 10 or so. Also I beleive yours has the option of running 85% ethenal. Just incase you feel there's a shortage of oil in the world.