No guarantees that this way of doing it will work for anyone else, or on anyone else's vehicle. Everyone should of course use their own best judgment about their own mirrors. But the following is a record of my own journey in learning to adjust mine. I was used to driving a regular car before this, so it was a learning curve for sure.
This is how I adjusted the mirrors on my Chevy Express van. It has what I believe are called "vertical mirrors" but what that really seems to mean is it's got a normal mirror that's basically the same as I'm used to with a regular car -- and then it has a horizontal strip of differently-curved, separately-adjustable mirror below that.
I'm going to be talking about what I see, from my point of view, as cars come up behind me and pass me. They start out when they're far away being visible on the inner top sides of the main mirror, and as they get closer they go towards the outer bottom, and when they disappear off the outer bottom of the main mirror, that's when they're in the blind spot of the main mirror.
So now the challenge is: once the cars are off the outer bottom of the main mirrors, once they're in the blind spot of the main mirrors, then how do I pick them up using the lower mirrors?
The first thing I had to do was to adjust the lower mirrors all the way as far towards the outside as they would go. As far left as possible on the left mirror, as far right as possible on the right mirror. I'm already at a disadvantage because the car is now off the outside edge of the main mirror. If I'm gonna pick up that car on the lower mirrors, those lower mirrors have got to be way far over to the outside.
The second thing I had to do was to adjust the lower mirrors "down". Way down. I don't need to be able to see anything out of them normally. That's what the main mirrors are for. I want to give myself the best chance at seeing cars that are off the bottom of the main mirrors. The lower mirrors need to be down, down, down.
At this point I was basically done, with the drivers side mirror. The drivers side mirror is much more forgiving. I found that on the drivers side, cars would fall off the outside bottom of the main mirror and reappear around the top middle of the lower mirror, and once they fell off the bottom edge of the lower mirror I could see them alongside my window.
With the passenger side mirror I wasn't done yet. Cars would fall off the bottom edge of the lower mirror on the passenger side, but they wouldn't yet be visible alongside the window. So I had to adjust the lower mirror on the passenger side, EVEN FURTHER DOWN.
But then I had a problem on the passenger side, because then there was a gap between when the cars fall off the bottom of the main mirror, and when they reappear on the lower mirror. So the way I handle that is by ducking my head. When I'm changing lanes to the right, first I check the main mirror. If that's clear, I check the lower mirror, and I also duck my head down and check the lower mirror again. That shows me the gap that I'm missing between the main mirror and the lower mirror. If it's still all clear, and if nothing's visible out the window, then I change lanes.
This is how I adjusted the mirrors on my Chevy Express van. It has what I believe are called "vertical mirrors" but what that really seems to mean is it's got a normal mirror that's basically the same as I'm used to with a regular car -- and then it has a horizontal strip of differently-curved, separately-adjustable mirror below that.
I'm going to be talking about what I see, from my point of view, as cars come up behind me and pass me. They start out when they're far away being visible on the inner top sides of the main mirror, and as they get closer they go towards the outer bottom, and when they disappear off the outer bottom of the main mirror, that's when they're in the blind spot of the main mirror.
So now the challenge is: once the cars are off the outer bottom of the main mirrors, once they're in the blind spot of the main mirrors, then how do I pick them up using the lower mirrors?
The first thing I had to do was to adjust the lower mirrors all the way as far towards the outside as they would go. As far left as possible on the left mirror, as far right as possible on the right mirror. I'm already at a disadvantage because the car is now off the outside edge of the main mirror. If I'm gonna pick up that car on the lower mirrors, those lower mirrors have got to be way far over to the outside.
The second thing I had to do was to adjust the lower mirrors "down". Way down. I don't need to be able to see anything out of them normally. That's what the main mirrors are for. I want to give myself the best chance at seeing cars that are off the bottom of the main mirrors. The lower mirrors need to be down, down, down.
At this point I was basically done, with the drivers side mirror. The drivers side mirror is much more forgiving. I found that on the drivers side, cars would fall off the outside bottom of the main mirror and reappear around the top middle of the lower mirror, and once they fell off the bottom edge of the lower mirror I could see them alongside my window.
With the passenger side mirror I wasn't done yet. Cars would fall off the bottom edge of the lower mirror on the passenger side, but they wouldn't yet be visible alongside the window. So I had to adjust the lower mirror on the passenger side, EVEN FURTHER DOWN.
But then I had a problem on the passenger side, because then there was a gap between when the cars fall off the bottom of the main mirror, and when they reappear on the lower mirror. So the way I handle that is by ducking my head. When I'm changing lanes to the right, first I check the main mirror. If that's clear, I check the lower mirror, and I also duck my head down and check the lower mirror again. That shows me the gap that I'm missing between the main mirror and the lower mirror. If it's still all clear, and if nothing's visible out the window, then I change lanes.
