A few weeks ago I re-shimmed my valves. After guaging the lash I found that 4 valves were near the middle of the acceptable range while the other 20 were at the loose limit of the range, and maybe a few were over. So I decided to re-shim all 20 which ment I had to basically add .002" to each shim. I moved a couple around and then placed an order with Dan for the other 18. Immediately I noticed the truck turned over faster and started quicker. The turning over faster pretty much ruined my weekend as we went camping up in VT and I felt I had done something wrong and a loss of compression was the reason for the faster turning over. Upon returning home I pulled the valve cover off and rechecked my valve lash. They were all right in the middle of the range, whew. Other things I've noticed is a lower startup idle, no startup rattle at all and the elimination of some slight pinging I had, I did also do the 180k tuneup so it's probably not all the valve lash. I realise that the .002" will increase the lift and duration, but I'm having an issue thinking it's doing it all. I've driven close to 1700 miles sisnce this and the truck is running great. If you haven't check this and put it off as I have you might take a little time out and check your's.