ok, so the second to last trip i went out on, i couldn't keep my engine warm b/c of a bad thermostat. as a result, i had a lot of blue smoke because my engine wasn't hot enough to burn the fuel efficiently. got my thermostat taken care of now. i went out yesterday, and when in 4-low, when i do engine braking, i still get a bit, not much, of blue smoke. is this normal? if not, could it be related to my engine timing due to my timing possibly (don't know) being one or two teeth retarded? speaking of smoke, does a healthy 6.2 spew any black smoke under a load? mine doesn't, and i'm thinking it should. i'm wondering if this could be a result of perhaps having the timing retarded as stated above. any thoughts?