-- Trade-ins from the Cash for Clunkers program are piling up and auto recyclers are seeking more time to meet the deadline for disposing of all those vehicles.

At some places, Ford Explorers, Chevy Blazers, Chrysler Town & Country minivans and other popular clunkers are parked bumper to bumper on several acres, many marked "C4C" on their windows, waiting to be drained of fluids, stripped of valuable parts and eventually flattened for scrap.

"I've got a parking lot of almost 4,000 vehicles right now," said Harry Haluptzok, chief executive of John's Auto Parts in Blaine, Minn., near Minneapolis. His business typically dismantles 100 vehicles per week, but the workload has now more than doubled, and Haluptzok hired 10 more workers to keep up with all the extra vehicles.

Under the program, the cars are required to be crushed or shredded within six months of the date the vehicle is transferred from the dealership. Recyclers say the deadline, even a few months away, will be hard as they try to remove spare parts such as transmissions, front and rear axles, starters and alternators.

"True recycling is using something to its fullest potential and then recycling it over again by making it into steel and sending it out to become another engine or transmission or car," said Jeff Cantor, an auto recycler in Candia, N.H. "We're breaking that circle here by crushing good quality parts. We can't process them quick enough in six months."

Consumers bought nearly 700,000 new vehicles in late July and August through the program, taking advantage of rebates of up to $4,500 on new cars in return for trading in their older vehicles. Congress tripled the size of its original $1 billion price tag because of the program's popularity.

Used engines from the vehicles were required to be destroyed to promote improved fuel efficiency.

The American Recyclers Association, a trade group representing auto recyclers, said the six-month deadline to crush the vehicles was developed in line with the initial $1 billion program, but never took into account the additional vehicles sold when the program was expanded. The association met with the Transportation Department in late September seeking an additional six months to recycle the cars.

"We do have a lot of facilities that have two or three times the number of vehicles they could ever have imagined getting. They're trying to process these in addition to their regular business," said Michael Wilson, the trade group's executive director.

Transportation Department spokeswoman Sasha Johnson said the department was aware of the request and noted that under the regulations, "most trade-ins through the CARS program do not need to be crushed until at least early next year."

In metropolitan Los Angeles, Aadlen Bros. Auto Wrecking in Sun Valley brought in about 6,000 vehicles through the Clunkers program since early September. "At times, we were having to stack cars on top of cars -- it got unruly there for a little bit," auto recycle Nathan Adlen said.

Most of the vehicles on their 26-acre lot go into a self-service yard, letting customers find the used parts they need for their vehicles. A car typically stays there for a month, but many vehicles have gone to the crusher earlier than normal because of the influx.

In Minnesota, Haluptzok expected to receive more than 1,000 cars through the program but saw his load grow to nearly 5,000. Each vehicle needs to be drained of oil, antifreeze and other fluids and then properly recycled.

"If it's about recycling, the thing to do is to give us another six months and let us do them the correct way each time," he said.