The UAW’s delay in declaring a new four-year labor agreement with General Motors is stirring tension in some plants between production workers, who approved the deal, and skilled trades workers, who rejected it, holding up ratification.

There have been talks in the past 24 hours between UAW leaders and GM labor relations executives over the concerns of skilled trades workers, who generally make higher wages and work as electricians and machine techs, among other jobs. Some resolution is expected later today, according to sources close to the situation.

One production worker at a GM parts warehouse, who asked not to be identified for fear of retribution, said fellow workers are expressing resentment toward skilled trade workers.

“If we voted no and (skilled) trades voted yes, the union would shove it down our throats! They treat trades like gods,” a production workers was overheard saying, according to the source.

Another comment: “How many unions do we have? One for production and a more important one for trades?”

It’s been a week since the UAW disclosed that 55.4% of members at GM voted for the agreement. But 59.5% of skilled trades voted no. They are the electricians, pipefitters, millwrights and repair people who maintain the hundreds of machines that enable the manufacturing of engines, transmissions and entire vehicles.

The UAW, according to its constitution, was required to conduct meetings to learn why most skilled trades members opposed the agreement that will provide each of about 52,700 hourly workers with an $8,000 signing bonus and raises over the next four years. Those meetings occurred earlier this week.

The union’s governing body, the International Executive Board, comprised of President Dennis Williams, vice presidents and regional directors, is charged with determining whether the agreement is ratified or asking GM to reopen bargaining.

The latter option would be unusual. The process has already delayed payment of a $8,000 signing bonus to each of about 52,700 hourly workers at about 40 GM locations. It has deferred implementation of raises in their hourly wages, but spokespeople for both GM and the UAW, said workers will not lose money once the matter is resolved.

This is the second time since 2011 when skilled trades rejected a national agreement that a majority of all workers at a Detroit automaker approved.

Four years ago the same scenario played out at Chrysler. In that case, after an appeal process, then-UAW President Bob King declared the agreement ratified and it took effect.

The split reflects the changing dynamics of UAW politics. Skilled tradesmen once wielded more clout both on the factory floor and in the UAW’s organizational chart.

They make more money — generally in the range of $33 to $36 an hour. On occasion they also accumulated substantial overtime, especially when installing new tooling to transition to a new model launch.

They also once held substantial influence over their lower-paid co-workers on the line, especially at contract time.

But that influence has waned. There are fewer skilled trades people in most plants.

Automakers have pushed for greater flexibility, requiring the highly trained specialists to take on duties once regarded as outside the “lines of demarcation” defining various skills.

Management also in the past four to eight years has been able to assign skilled trades workers to the production line.