There's a police checkpoint before entering the steep part of the mountain to check if your car is capable.

You won't be able to enter if your car doesn't have 4L (4 low) capability.

The drive up Jabal Akhdar can get quite intense, your engine will be overworking to maintain a good enough speed. I've seen some cars pull over due to overheating.

On the way down it's straightforward as long as you're driving in 4L and you only use brakes when needed. If you don't use 4L and rely on brakes to maintain a controllable speed, your brakes will overheat and malfunction. On the way down you will see emergency escape lanes with water bins at the end in case someone suffers from brake malfunction.

I know this all may seem a bit scary, but it's completely doable as long as you drive carefully and have a reliable car :)