A stretch of the B4632 in Gloucestershire is being closed for four weeks to investigate whether its surface contributed to a fatal crash.
The car driver, a 47-year-old man from Worcestershire, died at the scene when his car collided with a van in May.
A police spokesman said one of the factors collision investigators will look at would be the newly-laid surface on the road near Weston-sub-Edge.
One lane will be closed with temporary traffic lights put at either end.
Det Supt David Sellwood added: "We have a responsibility to establish the reasons behind this crash, which resulted in a man's death.
"To ensure the safety of drivers we are conducting further tests on the road.
"We're hoping to begin these tests in the coming weeks after consultation with our partners."
