Before a new model of car can go on sale, carmakers and dealers have to clear inventory of its predecessor.

It's not uncommon for carmakers to offer significant discounts on the outgoing version to clear the way for the redesign.

As General Motors prepares to start production of the new 2016 Chevrolet Volt, it's doing exactly that to get its 2015 models off dealer lots.

DON'T MISS: 2015 Chevrolet Volt Production Ends To Retool For All-New 2016 Volt Launch

Buyers willing to stick with the old model can currently take advantage of major discounts on the 2015 Volt, according to CarsDirect.

Effective April 14, Chevy started a new $1,500 rebate for the car, more than doubling total rebates from $1,000 to $2,500.

Lease payments have also dropped $50, to $249 per month for 39 months. The yearly mileage cap is unchanged at 10,000 miles.

[EDITOR'S NOTE: As several readers have pointed out, this lease deal applies only to certain states. From the Chevy Volt site: "Special offer available for the residents of California, Connecticut, Massachusetts, Maryland, Maine, New Jersey, New York, Oregon, Rhode Island, and Vermont."]

2015 Chevrolet Volt

2015 Chevrolet Volt

In addition, the amount due at signing is now just $500, down from $1,449.

And drivers coming from competitive vehicles don't have to pay even that: Thanks to a $500 "conquest bonus," they pay nothing at signing.

Chevy is also offering 2.9 percent financing for 48 months on any 2015 Volt, or 0 percent on any remaining 2014 models.

CHECK OUT: 2016 Chevrolet Volt: 50-Mile Range, 41 MPG, Five Seats, All New (Photos)

There likely aren't many 2014 models left, but a large supply of 2015 Volts remains.

As recently as two weeks ago, GM was estimated to have a 200-day supply of the cars--much higher than the 60-day supply carmakers like to maintain.

The company sold just 1,874 Volts in the first quarter of 2015--down 48 percent from the same period last year.

2015 Chevrolet Volt

2015 Chevrolet Volt

Some of the downturn in sales may be due to the "Osborne Effect": Consumers waiting for the 2016 Volt they know is coming, completely redesigned in and out.

The standout feature of the new car so far is a claimed electric range of 50 miles, an improvement over the outgoing Volt's 38-mile range.

SEE ALSO: 2016 Cadillac ELR: More Performance, More Range, Lower Price

GM is expected to shut down 2015 Volt production at its Detroit-Hamtramck plant next month to retool for the 2016 Volt, and allow time to get rid of built up 2015 Volt inventory.

The 2016 Volt goes on sale in the second half of this year. While an order guide was released last week, pricing still hasn't been announced.

_______________________________________________

Follow GreenCarReports on Facebook, Twitter, and Google+.