BMW has dialed back its appealing complimentary maintenance plan to limit owners from transferring the coverage if the vehicle is resold.

Good for four years or 50,000 miles of free maintenance coverage, the plan can now only be transferred "a current or former spouse or spousal equivalent, child, sibling, parent, grandparent or grandchild," the New York Times reported.

The switch is in effect as of July 1 and applies for vehicles of the 2015 model year or later.

The automaker estimates that the complimentary maintenance plan amounts to around $2,000 in savings for the average 36-month lease, something that has become too pricey for BMW to maintain under the original terms.

"It's a very expensive program," spokesman Kenn Sparks told the Times, adding that it costs BMW "many millions of dollars" annually. Limiting the terms to transfer coverage was essential to keep the program going for original owners, he said.

The Times surveyed 30 popular auto brands and failed to find an overall trend toward limiting maintenance coverage; however, Fiat, Hyundai and Kia specifically also limit the transfer of free maintenance to secondary owners.

Hyundai offers a complimentary maintenance plan for its Equus luxury sedan: three-year or 36,000-mile coverage that can solely be transferred to immediate family members. Fiat also has a plan covering three years or 36,000 miles that won't transition if the vehicle is resold, while Kia only offers complimentary maintenance for its K900 sedan, covering three years or 37,500 miles.

Customers should look into what maintenance issues are covered by the particular plan, an expert told the Times.

"It may be more efficient for certain consumers to pay $30 at a quick-lube place than take their car to a dealership," said Jack Gillis, director of public affairs for the Consumer Federation of America and author of "The Car Book."

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