Single frame superliner dump?

I had an 81 that was a single frame,used it to haul crude oil.

 

I'd go on bigmacktrucks.com site Dino soar...those guys are all die hards there that wear bulldog underwear. There'll be plenty of guys there to answer whatever you need or want to know about a Mack from an AC to a Titan.

 

Can’t a dealer run the vin and come up with the original specs?

 

Now that Mack is Volvo, I have my doubts that they'd even take the time to help look up something that old, unless you stumbled across one of the dinosaur parts men there that are willing to dig into it more than the newbies.

I have 40 year old equipment and have a stand-by team of "gurus" I use in different capacities of truck parts and salvage yards to help locate obsolete things as I need them. Most of the new guys won't look past the monitor screen, while others with some age will be happy to dig into the archives...that's what I have experienced. It is getting harder, but as long as there's a few good men left in the business, it will still be OK.

 

Heavy Rears?
If its a 80's Mack and it has heavy Mack Rears they are either 44K or 58K, they both have a cone in the center of the outside of the axle, if they are 58K rears they came with 11/24 tube type rubber and have larger cones, either way i have never seen a Mack factory dump truck with those rears have a single frame, i am more farmiliar with the Rd686SX and the later RD 688SX, both had heavy rears and double frames.
The serial number and the letters after the model will tell you the identical spec of that truck, SX stands for extreme duty, Superliner was different then the RD, if its a RW713.................letter after that will tell you.