Lacroix began working for Triple Eight in the United Kingdom in 1999 and was a founding member of the company's Supercars activities four years later.
The Frenchman also returned to race engineering duties this year, teaming with Craig Lowndes following the squad's expansion to three cars.
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Triple Eight has confirmed that Lacroix will continue to work alongside fellow engineer John McGregor on Lowndes' car for the remainder of the 2016 season.
Lacroix's time at Triple Eight also saw him take a key role in the design of the category's Car of the Future platform ahead of its introduction in 2013.
His departure comes during the early stages of development for the next-generation Holden Commodore Supercar which will debut in 2018.
Michael returned to Australia at the end of 2014 following 21 seasons in F1 that also included stints with Lotus and Jordan.
A Triple Eight statement says that Michael will help develop its engineering group, which is set to be bolstered by further new players ahead of 2017.
“Taking a part-time mentoring role with the Team, Michael joins Triple Eight as the team rolls out a number of new engineering appointments over the next three months,” read the statement.
“Triple Eight is thrilled to welcome him into the team and looks forward to further developing the foremost engineering group in the Supercars category with his guidance.”