FYI, I am not a heavy equipment mechanic, or a mechanic for that matter.
I am a millwright and structural fabricator ( I glue metal together in funny shapes from plans in a clean shop environment for specific uses )
Different form of the normal structural welder.
I have no idea how I ended up doing this job except that covid destroyed the industry I was in. But I am figuring it out and it's not rocket science. Unbolt broken part, bolt new part on.
Until you have to start diagnosing issues, being a mechanic is usually pretty straight forward. Diagnosing emission issues can be quite tedious, but once you learn exactly how the system works it isn't too bad. However, now days most shops and mechanics just keep throwing parts at the problem until it is fixed. At times that is the only recourse, but I hate doing it.
We have been going round and round with an Eaton Fuller 13 speed Ultra Shift trans on a Western Star. I finally started throwing parts at it and I think we may have it fixed. It would shift fine here at the yard and on short test drives, but after an hour or two of driving it wouldn't shift anymore.
I will suggest that when you have hydraulic hoses made, the quality of the hose is important. And the guy crimping the fittings needs to get it right or they will pop off. Just because a hose says it is rated at 5800 psi doesn't actually mean it will handle it consistently.
I imagine that 12 way blade is controlled by electric over hydraulic. If so, that could be a little difficult to diagnose issues when they arise. Especially if it is a PLC type system. Old school all hydraulic controls are way easier systems to work on, but not user friendly like electric over hydraulic.
I was just talking with a co-worker this morning about how many guys drive semi-trucks or work in the oil field and have no idea how anything works. When something breaks, they can't even explain what is wrong with it. All they know is how to start the truck, release the brakes, and put the auto shift trans in gear. Only a few of them actually know how to drive without hitting anything! I don't understand people like that. Its about the same as a race car driver not knowing how to repair anything on the race car when it breaks down in the desert. Or a bike racer not knowing how to change a tire or change the air filter. Makes no sense to me because I grew up repairing everything. My dad never bought a new car or truck or motorcycle, we couldn't afford it. We always bought someone else's problems and had to fix them.
Good luck with the new career. Hopefully the industry comes back for you. We are seeing an increase in the oil field. One of our customers has 300 new wells planned for this year on a 60,000 acre lease. Hopefully we get most of the work.