The Transformers stayed completely silent in vehicle mode during the first 4 live-action films, until Hot Rod finally broke the trend in The Last Knight.

i was going to make a post on how ROTB FINALLY had them talk as cars, but then i remembered about this. never mind i guess.

Spoilers: ROTB EXCELS at this and I LOVE IT. It really helps sell them as characters even when in vehicle mode.

He's achieved something!🤣

Always Rodimus that breaks something.

Ice cream truck

You could argue Bumblebee “talks” in vehicle mode but that’s just because he uses the radio anyways.

"Fuck this robots in disguise shit tbh, I wanna speak up." ~ Hot Rod, probably.

I have a feeling it was a licencing thing. Odds are, the car companies didn't want to have their cars saying anything they didn't approve of. Especially knowing the dialogue in Michael Bay films

I hate this movie but I like how they at least hype up Hot Rod’s reveal. “At least tell me I was abducted by one of the famous ones.” “I am better than all of them.” Really highlighting how important Hot Rod is. No other autobot after the first one got this kind of buildup

I think The Twins were the first on doing so, in the Shangai battle while they were in ice cream truck mode.