Dealers are missing out on warranty and service plan business.
RAC Warranty claimed used car dealers do not have a structured approach in place for warranty sales.
Ian Simpson, sales and marketing director, said: "Every used car represents an opening for a dealer to sell an extended or upgraded warranty or service plan.
"But many simply do not introduce the products to the customer. There are thousands of lost profit opportunities passing by each week."
Simpson said that used car managers needed to ensure that their staff were properly trained in selling warranties and service plans, and that an incentive programme was in place.
"The recession means that customers are currently very receptive to the idea of buying an extended or upgraded warranty or a service plan because they want to avoid unexpected costs in the future.
"Dealers need to ensure that they are approaching the whole area of warranties and service plans in a structured and professional manner.
RAC Warranty is a new warranty company operated by the RAC in partnership with The Warranty Group, and was launched at the start of 2008.
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