The Lexus LS400 is a popular car, but as it gets older, parts start to break. The hood struts aren't a critical moving part of the vehicle, but if one goes out, it's certainly inconvenient. The hood struts support your hood when it's open, and if they go out, the hood won't stay up. Replacing the struts should take about 20 minutes.
Pop the hood and have a friend support the hood itself so it doesn't collapse.
Remove the bolt holding the hood strut onto the vehicle using an open-end wrench. This part of the strut can now be pulled off the car.
Use the flathead screwdriver to pop the clip that secures the other end of the strut to the hood. It's a metal clip that pops into place and it will take a little bit of extra effort to get the screwdriver in between the clip and the ball socket, but it will come off. Then remove the shock.
Clip the replacement shock onto the ball joint on the hood. Follow that with the metal clip that you just removed in step 3.
Bolt the bottom of the shock in place on the car using the open-end wrench. The assistant can now let go of the hood; it should be supported by the shock.
