The U.S. auto-leasing industry has likely lost $10.4 billion since 2005 because of overestimating resale values of vehicles leased, CNW Research said in a report issued on Thursday.

The use of low- to no-interest and low-payment leases by some captive finance companies raises warning signs for investors although the projected losses remain far lower than earlier in the decade, CNW said.

Subsidized leases that base low payments on puffed up estimates of the value of a vehicle at the end of the lease term are casting dark shadows around the edges as lease deals used to boost auto sales grow again, CNW said.

The cautionary note came as GM announced it had reached a deal to buy auto finance company AmeriCredit Corp and make it the core of an in-house lending arm.

GM said the acquisition would allow it to capture more subprime buyers and increase sales through more lease financing.

General Motors Co GM.UL and Ford Motor Co relied heavily on vehicle leasing programs in 2007 and 2008 even as residual values slipped and the automakers were forced to take massive one-time charges.

With the sharp tightening of credit during summer 2008 and a plunge in resale values of big pickup trucks and SUVs, Chrysler turned away from leasing, and GM and Ford sharply curtailed the practice. All lease vehicles now.

About 7 percent of GM's U.S. sales are through leasing, compared with a 21 percent industry average, and the automaker expects a modest increase in the percentage of lease deals it completes following the AmeriCredit acquisition.

Some low-interest and low-payment lease deals were offered to customers with credit scores well below 700, and one Toyota lease program required a score of 660, CNW said.

(Reporting by Bernie Woodall; Editing by Steve Orlofsky)