Partial strikes now are affecting all three of Korea’s major unionized auto makers, with shutdowns occurring at Hyundai Motor Co. Ltd., Kia Motors Corp. and GM Daewoo Auto & Technology Co. plants.

Hyundai’s labor union has notified management it plans to hold partial strikes next week for a total of 18 hours at each of the auto maker’s production facilities, Ward’s has learned.

“The hot issue is the union’s demand for a new shift system that will ‘eliminate’ the night shift and reduce production by four hours each day,” a Hyundai source says.

The union says it will strike for two hours on Monday, four hours on Wednesday, six hours on Thursday and six on Friday.

“The union’s proposed shift system is the most contentious point in our negotiations,” the source says.

Under the current setup, there are two 10-hour shifts daily, consisting of one “day” and one “night” crew.

“The union’s proposed ‘double day shift’ system would have two consecutive shifts of just eight hours each,” the source says. Each would start earlier in the day and “no one would work beyond midnight on the later shift.”

Workers would rotate each week between the two shifts, under the union proposal.

“We are running at 95% of capacity, and the proposed elimination of four hours of overtime production would have an immense impact on our operations,” the Hyundai source says.

In addition, the union wants the cut in shift length to come without a corresponding reduction in pay.

“They are asking for an 8.9% wage increase, bonuses and other types of compensation to offset the lost overtime pay,” the source says.

Kia workers went on strike Thursday over pay and improved working conditions. They stopped production for four hours on each of two shifts.

The workers also have refused to work overtime, a spokesman tells Ward’s.

“We estimate that the Thursday partial strike will cost Kia 2,250 vehicles in lost regular and overtime production with an estimated value of 30 billion won ($29 million),” the spokesman says.

“This is the fifth partial strike held by Kia workers during the talks. Cumulatively we have lost production of 10,000 vehicles valued at 130 billion won ($125 million).”

GMDAT workers held a partial strike on Thursday at production locations in Bupyeong, Gunsan and Changwon, a GMDAT source says.

The workers idled production for six hours on both the day and evening shifts. They also refused to work the regularly scheduled two hours of overtime on each shift.

There is a national holiday on Friday, but GMDAT workers also will refuse to work on both Saturday and Sunday, the spokesman says. This will causes losses of 18 production hours on both the day and evening shifts.