"I think there are too many trucks on the roads."
Translation:Je pense qu'il y a trop de camions sur les routes.
I think that "je trouve" is a slightly awkward fit here.
If you were writing a report, then fine. But if you were saying it to the other passengers in a car then I think you would run the risk of sounding pretentious.
(Said the pot to the kettle. 😊)
In my opinion, "je trouve" is a considered opinion, something that you have put some thought into, or something where you have the benefit of experience.