Risk Zone: Alongside My Tractor on My Left Side, Where I Can See You out My Left Side Window and in the Convex Mirror over My Tractor’s Left Front Fender

Last Edited: April 16, 2017 // by TruckerScape, Inc.

Seeing You

When you’re in the left lane next to mine on the open highway (typically on interstates or major highways with two or more lanes in each direction, in sparse traffic, usually in the countryside) or even in traffic, your speed will usually be greater than mine.  When you have advanced from alongside the rear of my trailer to the trailer midships (middle) section, then to the front of my trailer and finally alongside my tractor, your vehicle’s image has exited my large left mirror completely through its outer (left) edge while remaining in the small convex mirror below it and in the small convex mirror over my tractor’s left front fender, then finally has almost entirely exited through its outer (left) edge the small convex mirror below my large left mirror while remaining in my tractor’s left fender mirror.  Once primarily in the left fender mirror alone, the image has diminished significantly (stands out less well) within my total mirrored field of vision.

By the time you reach the rear of my tractor, your vehicle’s image has begun to leave the convex mirror below my large left mirror and has left almost completely when you’re alongside my tractor.  But at that point, in daylight the image in the left fender mirror is of secondary use because I can see you directly out my left side window.  At night or in other limited visibility conditions however, the reflection of your vehicle’s headlights in the fender mirror becomes more important in monitoring your position.

In the event that my speed is greater than yours and I overtake you from behind, I won’t need my mirrors as you progress from direct view out my windshield and then out my left side window, though your vehicle’s image will also wind up primarily in the left fender mirror along with a fragment of the rear of your vehicle showing in the convex mirror below my large left mirror.


This zone is one of the less risky ones alongside my left side, since you are more readily visible.  Also the relative distances our vehicles have to travel to enable me to move left into your lane are small.

This zone poses other risks.  True, you are able to see the road ahead of my truck.  However, in wet or snowy weather your vehicle may still be hit by water or snow thrown sideways from my truck’s steer (left front) tire, which could obscure your view of the road ahead and my view of you.  If my tractor should have a steer tire blowout, your vehicle may be hit by shrapnel and you are at risk from tractor control problems as I bring the truck to a stop.

Your vehicle will be alongside my tractor’s turn signal/emergency flasher light in front of the left cab door, but that light may or may not be in your direct or mirrored line of sight from your driver’s seat and the ambient (scattered) light from it is not very noticeable in daylight.  The turn signal/emergency flasher light in the left headlight cluster is also not very noticeable in daylight in this risk zone.  It is generally best to move out of this and other risk zones alongside my truck as soon as it is practical, safe and lawful to do so.

Changing Lanes to My Left

For routine moves to the left for situations such as emergency vehicles or highway maintenance equipment and personnel or other vehicles and people on the right shoulder, I should be able to move over behind you by slowing down while you continue ahead.  (Of course, this assumes that no other drivers are alongside me and behind you.)

In an emergency in the right lane and/or shoulder, I prefer that you continue ahead briskly while I brake hard to swerve to the left behind you.  (There may not be time for me to signal and you to notice.)  If we brake simultaneously, you will block me until you have cleared my trailer tail due to your shorter slowing/stopping distance.  Then I may or may not have the time and space to swerve ahead of you.  If I do, you benefit by being safely out of my truck’s slowing/stopping path.

Motorcycle Surprises

Motorcycle riders are noticeable in daylight, with their loud engines, often travelling in groups or pairs, generally passing on the left, knowing that they are more visible to truck drivers on that side.  I haven’t had many problems picking them up in my mirrors and directly out my left side window and front windshield, even when they are traveling at significantly greater speeds than my truck.  Fortunately, fewer ride in the dark.

Two incidents come to mind in which a single motorcycle surprised me on my left.  The first occurred on a dark night when a rider on a very quiet, seemingly lower powered motorcycle appeared out my side window without my seeing him first in my mirrors.  Driving along with my windows closed, I sensed something–it may have been the low hum of the engine before actually seeing him settled alongside my tractor.  Clothed in all black and barely visible, he was riding along the far edge of the left lane next to me where my left fender mirror did not pick up his headlight well.  He continued alongside for some time before finally moving ahead.  I figured he must be a young rider unaware of the risk he was incurring.

The second incident also involved a young rider who had a young lady passenger.  He blasted by me in the left lane before I saw his motorcycle–it didn’t matter that it was in bright daylight–at a speed I estimated to be 100 mph (miles per hour).  I rarely report aggressive or reckless driving but I did call in this case, with the rider showing no signs of slowing down.

I have been fortunate not to hit those two or any other riders.  Other truck drivers have not been so lucky.  I have seen several sickening motorcycle/truck accident scenes with riders, so vulnerable, strewn along the roadside.  No doubt the truck drivers involved felt absolutely devastated.


This zone is one of the less risky ones because a truck driver can see your vehicle directly out the cab’s left side window and you have a relatively small distance to advance out of the way in an emergency.

There are still a number of reasons not to settle in this risk zone, including the possibility that in daylight you may not instantly notice a truck’s turn signal/emergency flasher lights.

As a general rule, move out of this and all other risk zones around a truck as soon as it is practical, safe and lawful to do so.

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