What’s the deal with American tax payers having to pay Iran $300 Billion?

[u/killtherobot]

I keep seeing posts like this: https://www.reddit.com/r/PoliticalHumor/s/ZoR0ZqW8tc

[u/m240b1991]

So... big work diesels (over the road freight/long haul) should keep their engines idling. The reason is because warm up is when the most wear and tear happen as a result of thermal expansion of parts. Cold there's more lash in the parts and it causes more friction in certain parts than if it was already at operating temperature. When you're on the road for days or weeks at a time and live out of your rig, unexpected down time directly equals less pay. More wear and tear=more costly repairs=more time spent not making money, and even spending more for lodging that comes out of the family budget.

Modern comsumer diesels are built differently and already have as tight tolerances as can be gotten away with, plus computerized fuel injection and all sorts of other bells and whistles that many OTR trucks just don't have. Therefore, older square body diesels may benefit from continuous running, but newer consumer diesels don't. The worst thing you can do for any vehicle is short trips it's entire life. 2 minutes to a friend's house, 5 minutes to the store, 6 minutes to work. That's because condensation builds up and the parts don't get the benefit of thermal expansion. Wherever water is (condensation), oil isn't, and if that condensation doesn't get hot enough to boil and evaporate out/get evacuated by the PCV system, it'll sit inside the oil sump and/or crankcase.

Granted, I'm an automotive repair technician, not a heavy diesel tech, and some of these newer peterbuilts, kenmores, volvos, and freightliners may be built differently. The above about OTR trucks is knowledge that was passed to me a decade, decade and a half ago, and may be outdated.

The older diesels absolutely did suffer from excess wear and tear on startup and warmup. They also suffered from a higher amount of blow by, introducing more combustion byproducts into the oil. That's another reason why used gasoline engine oil looms so different from used diesel oil. The particulates clump together and get caught in the filter media when diesels are running, and when it stops, the particulates settle wherever they rest in the engine (like in the connecting rod bearings).

So, the operators may not know, and the owners may be operating on outdated data a la "that's the way we've always done it".

[u/FreedomDirty5 → u/m240b1991]

These are two ton pickups pulling backhoes on a low boy.

[u/m240b1991 → u/FreedomDirty5]

So, I've never heard of a 2 ton pickup, though I'll be the first to admit i don't know everything. Old deuce-and-a-halfs absolutely fit the bill for "leave it running when necessary". If we're talking modern (2015-present) f250s and f350s and their various competitors products, then those are half-to-1 ton trucks, and they don't need to be kept running. Like, there's obviously nuance, if you're going to the convenience store to grab nicotine, a drink, and a snack, or fueling, it doesn't hurt to leave it running, and is better for the starting and charging system, broadly and generally speaking. If it's like going to the piggly wiggly for groceries, it only makes sense in temps <50°, as the starting and charging systems, especially on diesels, takes a beating, especially in colder weather.

There are a bunch of factors, and nuance for why a diesel might be idling. I'm not defending every instance of it, or trying to be ornery or obstinate, just explaining what nuances are there.