Mark T

That's a cool old B Model, does that have a Mack transmission in it ???  Quadraplex was kinda fragile with a 300. I ask cause you mentioned crawling underneath it when it was stuck in gear ?  If it's a Mack 5 and a 4 way behind that then that's a little more durable with the 300.  That old girl has air assist steering too I see.

Also, I'd imagine a fan on that no matter what type can draw 50+ HP if it's full on.

Fan is stuck on ????  Air clutch ?    I've found when a fan stays on and the engine doesn't run at the right temperature it never gets all the condensation out of the EGR cooler.....which makes it try to open the EGR valve more (and bleed off manifold pressure)  Temperature is critical to everything working and if it's too cool it won't really think it has anything wrong with it. (no codes)  If it is an air fan clutch ??  often the out of tank regulator (cut off) can be malfunctioning ....again, no codes.

That thing is shot. Something went through it that wasn't supposed to (dirt...filings ???)  wrist pins are going to be just as worn too .

(lol)   I think it's actually a boost leak that makes the tip fan work.   well kinda anyway

IDK if that Superliner has a V8 or not.....but if it did, I'd enjoy smoking a new X15 or or some 6NZ

Wasn't there a post on here a little while back about identifying a mixer from a small picture ?   Think he could find his answer here .

I believe that's an F model grill someone put on an R model.

Might be the crankcase pressure sending unit. 

"slugs "   that's a good one (lol)    An E9 that ran like it was supposed to ????  

I feel a little bad for the guy wondering what that sound is (lol) 

I've had 20000 pound axles break like that.  I'm convinced someone never had the correct height in the first place.  Lots of geometry in the mounting.   Just an FYI.  Small bags like those on a 13000 pound axles...less volume . Hence the @ 60 psi only yields 7K. Where a bigger volume bag 60 psi might be closer to 20 K

Ever think about smaller tires ?