After two years of supply chain issues and reduced inventories, carmakers are finally starting to expand their stock.

But rising interest rates have reduced demand. Ford Motors, for instance, said it expected to have 45,000 unsold cars. To stifle inflation, the Federal Reserve has hiked interest rates five times this year and indicated more increases are likely.

"The irony for the auto market is that just as the industry is poised to start seeing volumes increase from supply-constrained recession-like low levels, the rapid movement in interest rates is reducing demand," Jonathan Smoke, chief economist at Cox Automotive, an automotive services firm, wrote Wednesday. "New cars may finally become more available just when most Americans can no longer afford them."

Cox reported that the rates for new vehicles and used car loans each rose 2 percentage points. The new car loan rate is 7% and a used car loan rate is 11%, Cox reported.

With the new vehicle prices skyrocketing, used cars have gained traction.

Cox's Manheim Used Vehicle Value Index, which tracks prices of used vehicles sold at its U.S. wholesale auctions, reported a 3% decrease in September compared to August and 13% since January.