Keith Brock announced today that he is leaving Wessex Garages after 24 years with the franchised dealer group.
Its new managing director is Chris Wiseman, who has worked alongside Brock for the past 22 years in a variety of roles, including operations director and latterly deputy managing director.
Following a phased handover this month, Wiseman will begin as MD on November 1.
Brock said: "Wessex Garages has been a major part of my life and in 24 years I have worked with some talented individuals and teams developing friendships along the way with employees, business partners and customers.
"I would like to formally thank all who have helped me and my valuable teams build the company to what it is today."
Japanese automotive group VT Holdings bought Wessex Garages in 2016 from its founder and chairman Steve Patch, who together with Brock had grown the business from a single site in Bristol to an AM100 dealer group achieving more than £150 million annual turnover from multiple sites spanning from Bristol to Gloucester and Cardiff.
Wiseman said: "I am delighted to be taking on the role and look forward to a period of stability and consolidation in todays uncertain economic climate.
"We are in a strong position to prepare for the next phase of growth with a clear business vision, based around the retention and engagement of our tremendous teams while building on the key foundations and historical success"
Kazuho Takahashi, chief executive of VT Holdings, said Brock "was instrumental to the growth and brand representation which we have today" and has been key to the purchase and transition of Wessex Garages into VT HOldings, including integrating its worldwide accounting policies.
"I would like to thank him for his expertise and professionalism throughout. We wish him well for the future," he said.