definitely look at cab mounts. they seem to rust out on them. mack paint never seems to last on frames. after a year our straight trucks has...
yes just had rocker shaft bolt break on one of our trucks and caused cam damage.
your 3-5 code is for engine brake output #1 . could be that solenoid is bad or wire came off under valve cover. both very easy fixes.
try pressurizing fuel tank while you start it.
the best thing to do is replace the connector for the blower switch. macks have been notorious for burning up control panels and only solution I...