This is an awkward composition that relies on the tones to hold it together.  Usually the greatest tonal contrast is in the foreground and to create the illusion of distance in the background the darks become lighter and the lights become darker.  In the illustrated painting the foreground is mostly in shadow and the strongest contrast (which draws the eye to the middle ground) is saved for the truck in the sunshine.  If a painter is uncertain about the success of the tonal design tipping the painting upside down will allow a view which is purely a judgement of the tones without the brain registering the objects - merely looking at the pattens