Coal trailers are crazy

[FordGT90Concept]

I've pulled several with my fully upgraded Volvo FH16 (6x4 configuration) and they act like they are way heavier than 23 tons. If I am going faster than about 40kph around a cloverleaf turn, it wants to either tip the whole truck over or drive it into a wall. It's also extremely unstable at higher speeds around bends. There's other heavy loads that weigh the same (like Pressure Tanks) and they don't bully the truck around like coal does; moreover, despite weighing as much as other "heavy or oversized loads," coal doesn't get the same bonus they do. Something is very whacky with coal and it needs balancing (pay out more or lessen its physics).

If it is unstable because of the shortness of the trailer, then perhaps it should be made into the longer, side-dump variation that is common in North America.

[Baja_002]

There are some "bugs" with those trailers but they are not far from truth actually. Those trailers are shorter than other trailers, have higher positioned gravity center etc
+ there is no effect for "moving" material in ETS 2 so you can drive fuel, water or any liquid trailer without proper effect.... Slow down using either retarder or engine braking for smooth result, slowly accelerate as you exit corner and you'll never have problems

[FordGT90Concept]

You're right that it is because of the high center of gravity compared to other loads. There is sensical ways to solve that problem though, like these trailers:
[ external image ]
They carry the bulk of the weigh between the tractor and trailer axels (or slightly above) and they unload by dropping the cargo through trap doors on the bottom.

If there is no intention to change the design then they should at least be given the "heavy or oversized load" flag so they pay better for the hassle.

[n4gix]

One tip for smoother and better curves; slow down slightly before the curve, then accellerate slowly through the curve, so that you have constant and steady "pull" on the trailer's kingpin.

In simpler words, don't let the trailer "push" you through the turn; but force the truck "pull" the trailer through the turn.