Try these curated collections

Box truck or box van back view isolated on white background,
Cargo box or steel box for storage and transport cargo and high volume of goods product, clipping path include in file.
White steel door of car truck container
open truck trailer
Box truck or box van back view isolated on white background,
Cargo box or steel box for storage and transport cargo and high volume of goods product, Small cargo container delivery service.
Van car open door, back view. 3D rendering
Box truck or box van back view isolated on white background,
Cargo box or steel box for storage and transport cargo and high volume of goods product, Small cargo container delivery service.
The open rear doors of a lorry
Van car commercial trailer, back view. 3D rendering
Back of Delivery or Moving Truck
Rear view of new white cargo truck
Back doors of new white cargo truck isolated on white
open trailer
Back of trailer truck icon vector in trendy flat style isolated on white background
Empty van with open doors an light inside Empty van
realistic cargo van. front view; side view; back view.
Empty yellow moving truck with blue dolly in back.
Generic American red semi truck with semi trailer with opened back doors from the back right view, photo realistic isolated 3D illustration on the white background.
Two New Box Delivery or Moving Trucks
The image of back part of a van
Cargo container on back trailer and towed by front tractor,  Cargo container or shipping container for shipment storage and transport goods product and raw material, Vector illustration design.
Moving Truck with Boxes. Back side of the loading truck. Cardboard boxes inside and outside the vehicle.Packed interior furniture and cat. lettering moving home qoute.Vector cartoon style illustration
Truck for transportation cargo. Vector illustration. Isolated on yellow background. Cartoon truck. White truck. Delivery of cargo
white open truck
realistic trucks set. front view; side view; back view.
Closed back doors at delivery truck
Driver opens the door on trailer of parked truck. Lorry parked in the countryside. Beautiful landscape at background.Back view Slow motion Close up.
Truck's back door locked with a key
white truck
Back view of cargo container on back trailer,  Cargo container or shipping container for shipment storage and transport goods product and raw material, Vector illustration design variety color.
Open delivery truck with cardboard boxes. Isolated on blue background. Transport services, logistics and freight of goods. Flat style, vector illustration.
Blank space on back of truck perfect for your advertisement
Back view of cargo container on back trailer,  Cargo container or shipping container for shipment storage and transport goods product and raw material, Vector illustration design.
Cargo container on back trailer and towed by front tractor,  Cargo container or shipping container for shipment storage and transport goods product and raw material, Vector illustration design.
realistic truck. front view; side view; back view.
loading dock
realistic truck. front view; side view; back view.
Safety lock on the back of truck, transport and vehicle
Delivery truck. Doors can be opened, colors can be changed, the elements are in the separate layers. I'd recommend to rasterize each vector layer before exporting the file to PSD format.
Truck trailer rear view icon. White background with shadow design. Vector illustration.
Light truck (Set #14)  in vector . 

Optimized approximately to 166 x 90
Truck (Set #11) in vector.
Door of truck
Close up lock of Cargo Truck
Commodity shipping truck back door with a lock.
Truck (Set #12) in vector.

The  size is optimized approximately to 200 x 90 pixels (side view)
Delivery van.  Doors can be opened, colors can be changed, the elements are in the separate layers. I'd recommend to rasterize each vector layer before exporting the file to PSD format.
Vector illustration of truck loaded with boxes with bar-codes back view
realistic truck. front view; side view; back view.
Cargo Express Van Vehicle back view. 3D rendering
Cargo container or shipping container with strength for shipment storage and transport goods product and raw material between location or country, International trade equipment to exchange goods.
lorry under the white background
Truck trailer rear view icon on gray background, round shadow. Vector illustration.
Generic urban delivery refrigerator box truck with grey cabin, back right view with opened doors, photorealistic 3D Illustration, isolated on the white background.
Empty truck and trailer with open back door
Open back door of delivery truck parked outside store
Truck transportation with open door. Fast delivery or logistic transport. Easy colour change. Detailed trucks. Cargo delivering vehicle template vector isolated on white view Isometry front, back
Row back side of new trucks

Search for "truck back door" in these categories

white truck on rural highway with dramatic clouds, rear view, slightly blurred in motion
realistic truck. back view.
Truck for transportation cargo
Row back and face side of new trucks
Red shipping container cargo background, close up of container back door locked
Delivery refrigerated truck.  Doors can be opened, colors can be changed, the elements are in the separate layers. I'd recommend to rasterize each vector layer before exporting the file to PSD format.
Truck trailer rear view icon. Flat design. Vector illustration.
Shipping metal container on white isolate background.
Water color drawing of empty pick-up truck. Set of various views: back and side. Classic style, bright red colour. Handdrawn watercolour sketchy illustration on white background, cut out clipart.
A  truck with the national flag of Switzerland depicted on the back door carries goods to another country along the highway. Concept of export-import,transportation, national delivery of goods
Generic urban delivery refrigerator box truck with grey cabin, back view with closed doors, photorealistic 3D Illustration, isolated on the white background.
Boxes fall from truck as the back door is not closed. Truck drives at high speed and loses cargo. Сareless driver. Danger accident. Vector illustration, flat design, cartoon style.
Cargo container on back trailer and towed by front tractor,  Cargo container or shipping container for shipment storage and transport goods product and raw material, Vector illustration design.
Blue metal containers
van under the white background
Row back side of new trucks
backdoor of delivery or moving truck
Face of new black truck
back door of white van open with isolated white background
Row back and face side of new trucks
Back view of an empty cartoon truck with door open and closed
View of the entire rear of the school bus isolated on the white background
Horstmar, Germany - 24 AUG 2019: Generic European refrigerator semi trailer with opened back doors photorealistic isolated 3D illustration.
Retro pickup truck and van (1930-40th). Car icons in vector. The shadows are in the separate layer.
Three New Box Delivery or Moving Trucks
Moving and delivery truck. Back side truck for transportation cargo. Vector stock illustration in flat style isolated on white background
Delivery van.  Doors can be opened, colors can be changed, the elements are in the separate layers. I'd recommend to rasterize each vector layer before exporting the file to PSD format.
Vector Isometric icon set or infographic elements representing box truck with open and closed doors. Each vehicle in four views with different shadows. Low poly style
Truck for transportation cargo
realistic truck. front view; side view; back view.
White interior of the cargo area of the new fridge van. Refrigeration unit inside. Isolated on white.
Open delivery truck with cardboard boxes. Isolated on blue background. Transport services, logistics and freight of goods. Flat style, vector illustration.
white open truck
Delivery van.  Doors can be opened, colors can be changed, the elements are in the separate layers. I'd recommend to rasterize each vector layer before exporting the file to PSD format.
Horstmar, Germany - 24 AUG 2019: Generic European refrigerator semi trailer with opened back doors back side view photorealistic isolated 3D illustration.
Vector illustration of van under the white background
steel door security lock of a truck container, freight industry logistics.
Vans under the white background
Construction work van with door open in the back and working tools inside near construction site. Wood frame house project foundation framing in Irving, Texas, USA.
Food car yellow with open doors, back view. 3D rendering
Truck Trailer Rear View Icon. Thin Line With Blue Fill Design. Vector Illustration.
Passenger cars (Set #4).
Set of the car icons in vector.
open van isolated
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