He calculates a 3 percent rise in interest rates will reduce purchasing power by $2,500 while a jump of 7 percent would cut into consumer's purchasing power by $5,250.
"The threat of higher rates is a very real one and if they go up it will impact auto sales," said Wakefield.
Car sharing rising, China slowing
The latest study by AlixPartners highlights two trends that will alter how many see the auto industry.
Read MoreCar-sharing a growing threat to auto sales: Study
In the U.S., car sharing is a fast-growing trend that has many potential buyers now opting to car share instead.
By the end of the decade, an estimated 4 million people will participate in car-sharing programs, up from 1.3 million this year.
Meanwhile, the growth of auto sales in China will be slowing down throughout the rest of this decade.
"China is still the growth engine for the auto industry, but its growth is slowing," said Wakefield.
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By 2020, China auto sales will grow at an estimated annual rate of 3 percent compared to 13.5 percent increase in auto sales for that country last year.