General Motors has asked its dealers to help prevent customers from quickly flipping high-demand vehicles and adding high markups.

The Detroit automaker wants to ban customers who resell certain high-demand vehicles within 12 months from placing future reservations and orders. GM also plans to limit the transfer of certain warranties.

Steve Carlisle, president of GM North America, outlined the change in a letter sent to dealers. The letter noted that the 2023 Cadillac Escalade-V, Chevrolet Corvette Z06 and GMC Hummer EV pickup and SUV "high demand" models would be the first vehicles affected by the change.

Industrywide, dealers and consumers now charge hefty prices for vehicles amid scarce inventory. GM has urged its dealer network to sell and price vehicles fairly.

"When vehicles are quickly resold, particularly by unauthorized dealers or other resellers that do not adhere to GM's standards, the customer experience suffers and GM's brands are damaged," Carlisle said in the letter. "These changes are being implemented to ensure an exemplary customer experience, to ensure our brands remain strong, and to help prioritize ownership by brand enthusiasts and loyal customers."

GM will send a letter detailing the warranty transfer limitations and customer acknowledgment requirements to dealers this week, the letter said.