Caution Zone: Even With the Rear Section of My Trailer on My Left Side, and Two Lanes to the Left of Mine

Last Edited: July 28, 2016 // by TruckerScape, Inc.

Seeing Vehicles Two Lanes to My Left

When your vehicle is even with the rear section of my trailer (from the tail to the trailer tandems at their full forward position) and two lanes to the left of my lane, your vehicle’s image just shows up in the outer edge of my truck’s large left mirror.  When preparing to change to the lane next to mine on my left, I will be signaling and checking my tractor’s large mirror, the small convex mirrors and my direct sight lines on my left side for any traffic in that lane.  If that lane is empty I will check for vehicles moving into that lane from the next lane over (your lane) before initiating my lane change.

This second check for vehicle movement from two lanes over is not perfect.  Once a vehicle two lanes to my left has passed the rear section of my trailer (has advanced beyond the trailer tandems at their full forward position), it virtually disappears from mirrored and direct view until it is even with my tractor.  (My large left mirror and the small convex mirrors mounted below the large mirror and on my tractor’s left fender are aimed back along the sides of my tractor and trailer at the lane next to mine on my left, and their fields of vision out to their sides are limited.)

At night or in other dim conditions, headlight reflections on the outer rims of my small convex mirrors and ambient light may alert me to a vehicle in the left side blind area that I may be able to confirm by leaning backward and forward and side to side to alter my mirror sight lines.  However I prefer to wait to see if the vehicle will pull forward where it is more visible.  Once even with my tractor and in front of it, vehicles appear in my direct lines of sight out my left side window and windshield.

As a general rule it is safest to assume that when your vehicle is two lanes to the left of my lane, it is not visible to me until it is even with, or in front of my tractor.  One other important non-mirror detail:  I have a broader direct view out the left side of my cab (tractor) than out the right side.

When You and I Change Lanes

If you move one lane to your right to get alongside the rear of my trailer (from the tail to the trailer tandems at their full forward position), your vehicle’s image will shift from the outer edge of my truck’s large left mirror to the mirror’s center.  You will then be in a risk zone where I have to keep close track of you (see the Risk Zone:  Alongside the Rear Section of My Trailer on My Left Side Where I Can See You in My Large Left Mirror tip).  I will have to delay my lane change to my left until your vehicle is a safe distance behind my trailer or elsewhere out of all obstructive risk zones in that lane.  If I am able to pull ahead and/or you slide back, I will move into your lane only when I’m sure my trailer tail is safely past the front of your vehicle (see the Risk Zone:  Close and Directly Behind My Truck tip).

If you pull forward and get even with the midships (middle) section of my trailer (even with the trailer’s midships turn signal/emergency flasher light) before moving one lane to your right, I may not see your move until it is completed.  Once you’re in the lane next to mine on my left, your vehicle’s image will have shifted to a split position between my large left mirror and the small convex mirror below it (See the Risk Zone:  Alongside the Middle Section of My Trailer on My Left Side, Where I can See You Partially in My Large Left Mirror and Partially in The Small Convex Mirror Below It tip).

When you’re this far forward, I’ll be waiting for you to advance (hopefully briskly) through all the other risk zones in the lane to my left including the final one in front of my truck (see the Risk Zone:  Close in Front of My Truck and in the Left Lane Next to Mine and the Risk Zone:  Close and Directly in Front of My Truck tips).  I advise personal vehicle drivers to pass my truck whenever it is practical, safe and lawful to do so.

Once your vehicle is safely out in front of my truck, I will prepare to change to the lane next to mine on my left, signaling and checking my large mirror, the small convex mirrors and my direct sight lines on my left side for any traffic in that lane and then checking for vehicles moving into that lane from the next lane over.

If I begin to change lanes to my left at the same time as your move to your right, I will need your help in avoiding a possible collision.  Hopefully you will see my turn signal and cancel your move.  Although there is a better chance I’ll hear your horn as you advance towards my tractor on my left side, you should not rely on it to head me off (see the Hearing tip in the Truck Handling Characteristics and Limitations chapter).

If you defer to me, you will wind up alongside the midships (middle) section of my trailer (alongside the trailer’s midships turn signal/emergency flasher light), but obviously not in the lane you want.  I’ll be keeping track of you in my large left mirror and the small convex mirror below it and again expecting you to advance (hopefully briskly) through all the other risk zones in the lane to my left including the final one in front of my truck (see the Risk Zone:  Close in Front of My Truck and in the Left Lane Next to Mine and the Risk Zone:  Close and Directly in Front of My Truck tips).

Another clearing option is for you to move one lane to your left, returning to two lanes to the left of my lane.  Then if you slide back even with the rear section of my trailer (from the tail to the trailer tandems at their full forward position) or farther back, your vehicle’s image will return to the outer edge of my truck’s large left mirror or shift slightly towards its center.  I will change one lane to my left only after confirming that you have completed your move.  Once I’ve completed my lane change, you will be in one of the rear risk zones on my left side (see the Risk Zone:  Alongside the Rear Section of My Trailer on My Left Side, Where I Can See You in My Large Left Mirror and the Risk Zone:  Close Behind My Truck but in the Left Lane Next to Mine, Where I Can See You in My Large Left Mirror tips).

If you move one lane to your left and remain even with any part of my trailer extending from just forward of the rear section (beyond the trailer tandems at their full forward position) to the trailer midships (middle) section (even with the trailer’s midships turn signal/emergency flasher light), your vehicle will be largely out of my view.  This will cause me to be more cautious in moving to the lane to my left, even though the large mirror, small convex mirrors and my direct sight lines on my left side show that you’ve exited that lane.

Once I’ve completed my lane change to get alongside your vehicle on my left side, the position of your vehicle’s mirrored image will depend on how far forward of the trailer tandems your vehicle is.  If your vehicle is slightly forward of the tandems, its image will have just begun to move downward out of my large left mirror to the small convex mirror below it.  If your vehicle has reached my trailer’s midships (middle) section, its image will be split about evenly between the two mirrors (see the Risk Zone:  Alongside the Middle Section of My Trailer on My Left Side, Where I can See You Partially in My Large Left Mirror and Partially in The Small Convex Mirror Below It tip).

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