seyser

I don't think there is anything in particular that you should look for with these trucks. They are simple reliable old machines the will last many years with even a little care. Now with that being said here are some things I would look for. 

Frame cracks/welds and rust jacking if double framed.

Trunion condition. Make sure this is in good shape. 

Cab floor rust under mat and upper sill on roof.

Interior dash condition as they crack with age.

Headliner, Original plastic ones crack around screws.

Check wiring for cobble jobs and splices. If you see wire nuts used just walk away!

Drain air tank and make sure its not full of oil indicating a bad compressor.

Engine for oil or fuel leaks, check oil pressure and blow by.

Check date on engine serial tag and confirm it matches year of truck helping to indicate original motor or not.

Driveshaft U joints, Check for tightness.

Radiator condition, Look for excessive corrosion or damaged fins.

This will get you started, Good luck!

New steers installed. 
A couple photos hauling beans this week.

The Toyota is an original paint survivor that I purchased about a dozen years ago. It mostly just sits in the shed but I manage to drive it a couple times a year. Here is a photo from a few years back having a little fun putting it to work!

Sent a couple used 22.5 rims to get blasted and powder coated. They came back last week and my new steer tires were delivered as well. I’ll drop them at the tire shop to get mounted up this week. 

Both were born in 79. 

Hauled some beans into town again today. Here are a few quick pics. Gold dog reaching for the clouds!

Yea I asked my local Mack dealer and I think he said the oem is like $375 and still available. It’s a lot of money but I will probably just bite the bullet and pick one up after fall work. 
 

On a side note I hauled with it for the first time today. Took 2 loads of beans into the elevator.  Neither were full loads but it pulled well and has surprisingly good power. I go through a pretty healthy valley and only had to downshift into 4th gear.  I crested the hill at 1200rpm and just let it eat. 

My driver seat bottom was in poor shape so I removed it a couple weeks ago. I went ahead and pulled all the staples holding the cover onto the wood and inspected the foam, It was still in pretty good shape so that was good for reuse. I took everything including some original tan vinyl to the local upholstery shop. I choose some high wear tweed style fabric for the top and kept the original vinyl for the sides. It all turned out nice and should last many years.