CHICAGO (CBS) — It was the longest auto workers strike in 50 years.

GM workers may be back on the line, but some GM automobile owners are still feeling the ripple effects. The wait for parts to get the cars back on the road is taking months.

Robert Zambreno of Downers Grove has been tooling around in a drafty vintage sports car for months. The heat isn’t working but he is still waiting for parts to fix his other car.

The Chevy Malibu LT has been waiting on repairs and parked at a dealership since September.

It needs just one part — a timing valve. In October, 6000 people were waiting for one.

The six-week long United Auto Workers strike against General Motors this fall shut down plants and put tens of thousands of parts on back order.

Though the strike was resolved by late October, a GM spokesperson admitted varying degrees of backorders continue and that delays are longer then they would like.

“It’s incredibly frustrating,” said Zambreno. “I think it’s ridiculous it’s taken this long. I think they should have much better control over their supply chain.”

At C & W Auto Body in Lincoln Park, workers spend hours on the phone locating parts promised for delivery

“Parts that are on these trailers in a warehouse somewhere, and they tell us it’s two weeks out,” said C&W assistant manager Robert Carrasquillo. “Two weeks come and they say they still don’t have it.”

Carrasquillo said it makes it hard to keep his customers satisfied.

The strike led to $1 billion in lost wages for workers, and $2 billion in lost production for GM.

Dealerships are offering loner cars for those with vehicles under warranty, but those waiting for parts will continue to wait.

GM does not have a timetable when it will be back to its standard two-day window for parts.