I voted to close OBD2 protocol in trucks for being off-topic, but it was a coin toss. Is one or the other preferred in situations like this?
I suppose you could argue either way on Car electronics, but I felt that one was more off-topic.
I know this is a bit late, but anyhow... I would personally leave questions like the one in question open. Reason being that the OP is not asking "Are these two trucks compatible?" - which would be more border-line in my thinking. Rather, it is asking for information on how to figure out if they are.
In the case of asking specific cases, I think you have to go case by case. Sometimes, we might have to close some as simply too specific. However, even in the case of asking, "Are these two trucks compatible?" I believe we are producing quality material, albeit specific-case, and therefore, in the majority of cases, they should be left open.