Wheels on some Mods glitch out.

It's the modmaker's problem, not BeamNG development team's. Bug reports is only for reporting bugs of official content.

 

This problem happens on all cars if the tires take enough damage since they're the easiest to manipulate. Although I've had it happen many times on the body as well. Only reason I can think of is when the game reloads your car with the use of the insert key, it loads it from the model you were using instead of keeping one fresh in memory or loading it from scratch from the storage device, meaning if the car takes enough damage some parts might get lost and upon resetting the car when it loads the model from the one you just used it doesn't have the parts because some were missing. Obviously I could be horribly wrong but thats one of the most logical reasons i can think of. It'd make sense for them to do so because it saves on memory and makes loading times faster but might be another reason entirely.