So I have a 2004 F350 6.0 it has 152000 miles, so about 3 months ago it started to blow a little blue smoke, now whenever going up a hill or pulling a trailer it blows blue smoke when shifting from 1-2 and 2-3 sometimes when shifting from 2-3 it hesitated and blows quite a bit of smoke.. and ideas what is going on? It does not use any oil that I can tell, did a recent oil change and still was full. Any help would be appreciated thank you.