An Ontario man is suing General Motors of Canada on behalf of himself and other retired white-collar employees of the automaker.

The GM sign outside the Oshawa, Ont., plant. A retiree who worked at the plant for nearly 40 years is suing the company for rolling back post-retirement benefits.The GM sign outside the Oshawa, Ont., plant. A retiree who worked at the plant for nearly 40 years is suing the company for rolling back post-retirement benefits. (J.P. Moczulski/Canadian Press)

The suit claims GM Canada violated its contractual obligations by rolling back post-retirement benefits in recent years.

The lead plaintiff, Joseph O'Neill, belongs to a group representing more than 3,500 retired employees of the Oshawa, Ont.-based company.

O'Neill was a GM employee for nearly 40 years, starting in 1964, and was a manager at the Oshawa Truck Plant when he retired in 2002.

The suit calls for the court to restore the retirement benefits in full or, if that's not possible, to partially restore them so all retirees get a proportionate share.

A GM Canada spokesman says the company won't be commenting because the matter is before the courts.