Lately, I've been seeing a number of ads in my Feeds about a certain aftermarket high-CFM auxiliary fan being sold either as an upgrade to the OE aux fans or as a bolt-on to complement vehicles with traditional belt-driven fans. My first reaction was, these fans make a lot of noise and seems overkill.

But then I recalled this video from 2023 about "stalled" cars going to Baguio in bumper-to-bumper traffic (credit to its owner): https://www.facebook.com/share/v/19arRvX9LR/

Based on the video and despite what the owner is saying, it's not perfectly conclusive whether or not every car shown on the side of the road suffered from overheating.... BUT, it does look like it at face value (hood's up, some people tinkering in the vicinity of the radiator, etc.). Whether that's wholly or partly true, I want to hear your take on it.

I've always believed that most modern cars are designed to operate in virtually any conditions. My hypothesis however, is that the high elevation, and hence lower air pressure and density, has a lot to do with it. Less air molecules makes the cooling system struggle to shed heat. So maybe those aftermarket aux fans CAN help under these conditions.