Engine oil additives may promise to improve your vehicle’s performance, but many are actually harmful, causing severe engine damage over time. Take the notorious PTFE Teflon-based additives, for example—despite claims of reducing friction, these additives only clump and clog oil passages, leading to engine failure. Let’s dive into the most dangerous ones you should avoid, and I’ll reveal the single most effective one that I’ve personally tested. Let’s watch the video to find out more...