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Comment by Arrath | Hacker News Reader

Though I only gave it a quick search and it seems annoying difficult to find straightforward spec sheets for semi tractors like you can for any piece of CAT equipment, [0]"As we highlighted above, there are several ways to measure a semi-truck’s weight, and the maximum legal weight for a fully-loaded semi in the United States is 80,000 pounds. The lowest unladen weight is roughly 25,000 pounds, but will typically be closer to 35,000."

So, 10,000+ pounds for the power pack alone is a sizable chunk of the maximum allowable weight, and could potentially eat into the allowance for cargo, more so for restricted routes like older inner city bridges with tight weight limits and the like.

[0]https://www.jdpower.com/cars/shopping-guides/how-much-does-a...

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Tesla does get a small buffer for the battery size, due to EV trucks being allowed 82k instead of 80k lbs max.[0] Doesn't save the entire extra budget though.

[0]: https://afdc.energy.gov/laws/11682

> NGVs and PEVs may exceed the federal maximum gross vehicle weight limit for comparable conventional fuel vehicles by up to 2,000 pounds (lbs.). The NGV or PEV must not exceed a maximum gross vehicle weight of 82,000 lbs. (Reference Public Law 116-6 and 23 U.S. Code 127(s))

I’m curious how often fully loaded semis hit 80000 lbs. a quick google seems to show me maximum capacity instead of average/median weights…

Agricultural products, heavy equipment hauls, bulk materials, etc. regularly hit 80k pounds and above. Truckers picking routes to bypass scales is a meme for a reason.

Not at all uncommon, though my experience is with equipment rather than general containerized or palletized cargo.

e.g. a CAT D8T bulldozer weighs in at over 80,000lbs all on its own and they are often trucked around as a complete unit, so you're looking at 20-35,000 more for the trailer and tractor to haul it. Heavier pieces of equipment like D9's (108,000#) or D10's (145,000#) are generally 2-3 loads of chassis/tracks/blade&attachments.

Just an aside, a D9 is a real hellbeast. I got to drive one on some forestry work and there's not much out there that makes it stop moving. Gives me a stiff willy just thinking about it.

Both the CAT D9 and the Tesla Model 3 Performance advertise 450 HP.

Drivers being ticketed for overloaded trucks was a constant complaint in my childhood home back in IL, where the head of the household owned a concrete construction company.

Apparently the highway patrol would camp out in the industrial/shipping areas and watch for compressed suspensions/bulging tire sidewalls on big trucks as a monthly fundraising exercise.

Obviously there's a business incentive to move as much as you possibly can at once...

>watch for compressed suspensions/bulging tire sidewalls on big trucks as a monthly fundraising exercise.

I am unhappy with this description. An overloaded truck is a safety issue, and also a long term road-wear issue.

> I am unhappy with this description. An overloaded truck is a safety issue, and also a long term road-wear issue.

Sure, except this fundraising didn't stop the activity. It just took a cut from the profits, and the vehicles drove off AIUI. This was Illinois in the late 80s-early 90s I'm talking about...

It's not about safety. The 80k limit comes from limiting wear and tear on roads. Pretty much every semi truck is built to tolerate 120-150k without caring though wear and tear on the trucks really starts to increase a lot beyond that.

Some states have higher weight limits when the ground is frozen.

Any time you see a trailer that carries some sort of bulk good it is safe to assume that that trailer is right at the max weight.

EV trucks are allowed to have a maximum weight of 82,000 pounds instead of 80,000 for ICE trucks.

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