Is it normal to be this preoccupied with a hobby/interest?

In the Reserves, I work on the most common vehicle in the Army which is the HMMWV. There are many variants of it but with only minor differences. The HMMWV comes with a V8 and an auto torque converter 4-speed transmission and transfer case (naturally, because it is an off-roading vehicle) with a limited slip differential so you already know it has a high torque output by those virtues. The tranny has its own radiator so we don't experience a whole hell of a lot of problems in the department of wear and tear on those things unless the operator poorly maintained the transmission because they DO tend to burn fluid more often than a tranny on your average vehicle (it is 100% all wheel drive) so it requires occasional refill.

The other vehicle I work on with less frequency than the HMMWV is the LMTV (Light Medium Tactical Vehicle) with a massive 6 cylinder. I would compare them to small semi-trucks, maybe. Their transmissions are interesting in that they are button operated and are 7 speed. They aren't good for off-roading seriously fucky terrain but they off-road pretty well. The LMTVs use an air system to regulate tire pressure for traction. Basically it's a box in the driver's compartment side where you choose your terrain (highway, sand etc.) and once you've chosen it, the tires inflate or deflate as you are driving. It's very useful, actually.

Most of what I do on them is maintenance although I often have to do a lot of trouble shooting with electrical systems and ghetto fixing busted ass fuel lines. I've done a good amount of weird shit in that department.

As far as civilian vehicles goes, if I had to choose a specialty, I would say suspension work is my favorite and I love doing it. I'm a huge stickler about ride quality and handling (which answers your other question: I'm into rally cars, I have a Focus SVT but I love a good V8, my family is into Mustangs) and suspension work is very straight-forward. I can do electrical work (because I have had to) but I hate it. I've had to do a lot of emissions, fuel system and cooling related work. I would say transmission work is the field that I am the least experienced in, hence, why I buy manual transmissions... in the event that mine ever gets fucked up. Lol. I have studied automatics and holy shit-balls no. I have a textbook understanding of automatic torque converters but the dual clutch automatic and the pulley auto fries my mind.

I graduated from Diesel Mechanic school with honors and I am fairly experienced in my trade. I often have to teach newer soldiers to the unit the ins and outs of working on our vehicles so I know exactly what I know and what I don't know, I try to improve upon.

Oops, wait a minute... I think I know who you are now, but I dunno.

I was diagnosed with it at a teen but I rarely think about it.

To an extent, I agree with you in regards to the Capitalist aspect but that's more my hang-up about appreciating vehicles. It really burns me that there are so many people driving gigantic-ass trucks and SUVs that never leave tarmac when, for most people, their needs could easily be met by a sedan. But the truck is big and pretty and sexy blah blah...

If it helps you any, my certification is as a diesel mechanic and clean diesel is becoming one of the most environmentally friendly and sustainable methods of public transportation and to some extent, private transportation. Diesel burns cleaner because it is compression based rather than combustion based so not as many emissions, has a higher combustion point so a fiery diesel spill is unlikely (I have dropped cigarette butts in puddles of diesel without realizing) and due to these factors as well, it burns off (because it DOES eventually burn off like gasoline) much more slowly so one gallon of diesel takes you a hell of a lot further than 1 gallon of regular petro.

It's still fossil fuels, yes, and it's still not 100% environmentally sustainable, yes, but clean diesel public and private transport is a huge improvement from what it once was and it's a great bridge between old petro transport and electric/solar etc. transports of the future.

When those become big, I will gladly adapt. For the time being, though, the technology is so complicated that it is way beyond the level of most mechanics and there aren't any engineers who actually understand the whole thing so much as there are a shitton of specialists who work on each aspect separately which is what makes it so damned expensive along with the fact that the technology is not far along enough yet to be able to cheaply mass produce.

And don't get me fucking started on hybrid engines, those are as bad or worse as most modern petro engines, they just get better gas mileage. Altogether, the carbon footprint is the same if not worse.

TL;DR I'm on your side, just in a different industry. A lot of the work I do with vehicles in general is aimed toward energy and environmental efficiency as well. Wasted energy is wasted horsepower!

I talk to myself enough as is lol

Damn, that was smooth!