The 32-year-old from Preston in Lancashire was driving a silver Renault Clio, which was involved in a smash near Junction 20 northbound just after 4 am.
No other vehicles were involved.
Mr Harrison was pronounced dead at the scene. His next of kin are aware.
Sergeant Leigh McCulloch, Dumfries and Galloway Road Policing, said: “Our thoughts are with the man’s family and friends at this time.
“We are carrying out enquiries to establish the circumstances which led to this crash and would urge anyone who may be able to help to come forward.
“In particular we would be keen to speak to anyone who was on the M74 and may have dashcam footage.
“Anyone with information can call 101, quoting incident 0405 of 6 July.”
- Stock photo above
