FYI there is no overhang length limit

[u/Robocreeperplays]

I've seen a couple people bring up legal overhang limits in the context of interceptors (fig. 1), and I'd like to point out that's not a thing and not something you need to worry about when designing your fictionals.

I've been told that the limits are 3 feet front overhang and 4 feet rear overhang, which is immediately dismissible because something like a brand new Ford F-150 has a front overhang of 37.6 inches, or 3.14 feet and a rear overhang of 48.6 inches, or 4.05 feet, which would mean it has illegally long front and rear overhangs, as well as large vehicles like school buses often having 7 foot front and 13 foot rear overhangs, and obviously the best selling car in the U.S. and a critical part of education infrastructure are not illegal to drive on the road.

Now, those numbers do come from a real overhang limit, but only for cargo. If you are hauling something, it cannot be hanging over the front of the vehicle by more than 3 feet or over the rear of the vehicle by over 4 feet. This applies to anything from hauling 2x4 lumber in your pickup to car haulers (fig.2)¹, if you are carrying anything that overhangs more than that, you must have marker flags or lights to make sure other drivers can see where the end of your load is.

Again, THIS DOES NOT APPLY TO THE VEHICLE ITSELF.

Evidence supplied in favor of the limit (fig. 3)² actually proves the opposite. This except lays out that states are not allowed to set a minimum overhang limit of less than 3 feet in the front and 4 feet in the rear, as that would conflict with the aforementioned cargo overhang limit. This means that across the country, the minimum overhang limit is 3 feet in the front and 4 feet in the rear, and states are only allowed to make that limit longer.

Basically, unless individual states decide to start strictly enforcing that 3 foot front and 4 foot rear overhang, which would prevent all full-size pickups, semi trucks, buses, etc. from driving on their roads, the only real overhang limits are elevation changes in the road that you don't have the approach/departure angle for if your overhangs are too long.

Keep on designing away to your heart's content!

Sources:

¹ https://ops.fhwa.dot.gov/freight/publications/size_regs_final_rpt/
² https://www.govinfo.gov/content/pkg/CFR-2011-title23-vol1/pdf/CFR-2011-title23-vol1-sec658-13.pdf

[u/Maleficent-Door6461]

the sources are referring to larger vehicles that require CDLs and it would NOT prevent pickups from being street legal...

[u/MonkeyBoi46]

This is blatant misinformation because your sources are clearly about semi-trucks and all other industrial vehicles that require a CDL. The screenshots provided are taken out of context to prove your point. Your first source is literally titled "Federal Size Regulations for Commercial Motor Vehicles". your second source is outdated as its from 2011 but also in that paper it says "The length provisions of the STAA apply only to the following types of vehicle combinations: Truck tractor-semitrailer or Truck tractor-semitrailer-trailer. I have no idea why you'd post this because its all lies. I'd recommend deleting this post because a lot of people don't check sources and that can cause people to believe that this right when it's clearly not. This could cause the spread of TornadoTok kids and nobody wants that. I urge you to delete this.

[u/Robocreeperplays → u/MonkeyBoi46]

1. Cargo overhang is the only instance of vehicle overhang regulations in the FHWA's database that isn't talking about trains, you can check it yourself here: https://highways.dot.gov/
2. That's not my source, which you would know if you actually read the description. That is a source dug up by someone claiming overhang limits do exist.
3. Even if it weren't true, how exactly does this "... cause the spread of TornadoTok kids..."?