11 Jersey Barriers weigh roughly 45 000lbs, or 20 metric tonnes.

What's the incentive to lie if these things are now out in the wild and this will be easily verifiable?

Also, Tesla haven't ever mentioned the weight of the tractor, so I don't know where there would be a lie. The 82k lb GVWR is an industry standard, nothing specific to them.

Considering that these are now out in the wild being used by customers, there's not a whole lot of benefit to get out of lying and a lot of downside.

Most people who've worked the math out seem to be pointing out that the Semi weighs between 22-25k lbs, which is 4-5k more than a diesel. With the extra allowance in total weight, the penalty is pretty small.

If it's in bumper to bumper traffic, it will barely be using any energy, so it would give an increase in efficiency.

Cold weather negatively affects range, but that effect will be less significant than with an EV car, since some of the factors such as interior heating and winter tires play a much smaller part in energy usage on a Semi. The cabin may be a little larger than a car, but not substantially so the amount of heat needed will be similar. Semis don't switch tires in the winter.

Trucks do the vast majority of damage, but a difference of ~2.5%, which is about the weight of full fuel tanks isn't going to change that amount by an appreciable amount.

Especially since many states and provinces actually allow more than the federal standard, provided the axle count/configuration meets their rules. Michigan goes up to 164 000lbs with 11 axles and Quebec/Ontario are similar.