* Union says GM asks Cami plant workers to start talks early
* CAW workers vote Feb 10 on opening talks
* March 24 set aside for ratification vote
* Union reached pattern deal with Detroit 3 in Sept
TORONTO, Jan 21 (Reuters) - The Canadian Auto Workers union is recommending workers at a General Motors Co plant accept what it says is the automaker's request to open labor talks months ahead of a September contract expiry, believing it could help secure jobs at the southern Ontario site.
A union representative said on Monday that he believes GM wants a new contract earlier than planned so that it can lock in long-term costs before starting construction of a major addition to the Ingersoll, Ontario, plant.
The automaker has begun site preparation and moved "acres of dirt," said Mike Van Boekel, chairman of the Cami plant unit of Local 88 of the Canadian Auto Workers. Van Boekel believes the addition will house a welding shop, which would be a requirement for plant production of next-generation vehicles in two years.
The Cami plant, which last year produced more than 300,000 of GM's fast-selling Chevrolet Equinox and GMC Terrain crossovers, employs some 2,700 hourly workers.
Production runs 24 hours a day, six days a week, with mandatory overtime, Van Boekel said, but still has not kept pace with demand.
General Motors did not immediately respond to a request for comment.
There has been media speculation that production could move to Spring Hill, Tennessee, and Ramos Arizpe, Mexico, in 2015, Van Boekel said, but no such announcements from the company.
"GM has told us in meetings that they do plan on building where they sell, and GM is selling a lot of vehicles in Canada," Van Boekel said.
Workers will vote Feb. 10 on reopening talks and could vote March 24 on a new contract.
The union will seek the same terms as a GM contract negotiated in September 2012, under a process known as pattern bargaining.
Under that four-year contract, wages are frozen for existing workers for the first three years. Workers get a cost-of-living adjustment in the fourth year, and series of lump sum bonuses. New hires will start at a lower hourly rate than under the previous contract and take 10 years to reach the top level of the pay scale, up from six years previously.