That conclusion comes as GM dealers around the country begin repairs of faulty ignition switches, which affected 2.6 million vehicles. Dealers contacted by CNBC said they expect to receive new switches within the next day or two and start repairing recalled cars immediately.
Over the last two months, GM has worked with R.L. Polk & Co. to locate and notify the owners of the recalled models. Notices were sent in envelopes that clearly alerted owners that their vehicle had been recalled.
Still, many will ignore the prompt to take their car into a dealership, Gamache said.
"Despite hearing the news that their vehicle could be affected by a recall, or even receiving an actual recall notice, many consumers don't know what to do, do not have the time to get it taken care of, or may not feel like it is as important as it really is," he said.
Read MoreNo parts received yet to fix ignitions: GM dealers
One reason for inaction is the fact the recalled GM cars are older models—many were sold between 2003 and 2007—and are on their second or third owner.
Gamache said older models that have been recalled are often not repaired because the owner has less motivation to take the car in to get fixed.
As such, some dealers expect owners to trade in their car for a new one instead of getting it repaired.
In the words of one Chevy dealer outside Chicago, "A lot of these cars are on their last leg."