Career
At the age of 16, he joined General Motors as apprentice in the Opel technical development center in Rüsselsheim, Germany, and retired at the age of 61 by the end of the year 2003 as chairman and managing director of Australian General Motors subsidiary,, having served in the mean time in a number of managerial positions at Opel,, and General Motors internationally. Peter spent most of his early career working for General Motors"s Opel division in Germany as a vehicle tester and suspension engineer In 1976 Hanenberger was approached by General Motors-Australia to assist with suspension work on their vehicles, and with notice of a month from Opel, he was transferred there.
During that year he assisted with a new suspension tuning update for their cars, entitled RTS ("Radial Tuned Suspension").
Well liked by the people at for his genial and professional manner, Hanenberger left Australia to return to Opel in the early 1980s becoming General Motors vice president and group executive of Opel"s International Technical Development Centre (ITDC) in Rüsselsheim, Germany. In 1999, it was announced that Hanenberger was to be the new chairman and managing director of On assignment with in the 1970s, Hanenberger had assisted engineers with their "European look" design briefs, and upon his return in 1999, he implemented quality control and improved production engineering principles.
After discovering that the prototype Monaro had been built by a group of enthusiastic and dedicated engineers in their free time, Hanenberger encouraged the development of the prototype into production-readiness, and sought out export markets to guarantee the car"s production. Hanenberger also consolidated the maker"s exports programmes of its Vermont Commodore/WH Statesman/Caprice platform, and the cars quickly became favorites in the Middle East, winning numerous motoring press awards.
In 2003, he announced that he would retire, after spending about 45 years with General Motors.
Hanenberger retired to his home town of Wiesbaden.
As a farewell gift from, they made him a once only special Monaro. lieutenant is left hand drive (for Europe), with a special Pontiac GTO LS1 V8 engine. There was also a HRT0001 Monaro coupe Hanenberger had built as a special order company car when he was Chief Executive Officer. This was a black Monaro CV8 with the Callaway C4B 300 kW (400 hp) engine, GTO badging, unique interior trim, Herpes simplex virus brakes and HRT front and rear spoilers (same as HRT427) and was called "HRT Coupe 0001" this was the only "non-Herpes simplex virus" car to use a CB4 engine.