I had one years ago also. Got it at an auction pretty reasonable. Lack of tilt adjustment on rolling land made it nearly impossible to drive a post in straight. The drive wheels were made of laminated belting like material. Being used the drive wheels had weathered and wore quickly. Got frustrated with it and sold it
10 years later, bought a good, very little used Shaver HD-8 with hydraulic tilt. My neighbor had boughten a HD-8 with manual adjust tilt. Watched him drive around 100 posts and was constantly cranking on it. He told me if he had to do it over, he'd have gotten the hydraulic tilt, so that is what I looked for when I got mine.
I mounted it on my little '65 Ford 2000, being it was a one man job, wanted something easy to get off & on when aligning the line of posts. I'm pretty particular having a straight fence line. I drove around 400 5" posts with it through a mild winter when the ground was softer, had to in the shaley clay. Used 6" posts for braces and corners. Drove a little slower, but sure beat digging/tamping in by hand. Once lined up, kept it straight using a pocket level to keep it plumb. Only maybe 6 or 8 were not straight due to hitting larger rocks down a couple feet in the glacial till. Found out soon you're not bring it back to being plumb when that happens. Directions for them back then said not to sharpen the posts to make them drive easier. I did a couple tests posts before starting, sharpening one. The sharpened one did take off on its own driving crooked, and I had the point pretty much centered. The flat bottom post drove straight.
Only broke one spring on it during that time. A local John Deere dealer handled parts for them but was pretty expensive. Looked on the internet and found them for half the price at Kencove fence supply. I bought 2 figuring the other side may go at any time. Never needed it as the other side lasted through that job. Glad I did, just checked Kencove, and that $80 spring is now $292.00.
I still have it stored in the barn for just in case someday. It's not eating anything. If I never use it, it will look good on the sale bill someday.