Repairs at a new car dealership cost an average of 34 percent more than those at independent repair shops, resulting in $11.7 billion in excess costs to consumers annually, according to a new study released by the Automotive Aftermarket Industry Association (AAIA).

The report, "Vehicle Repair Cost Analysis: New Car Dealerships vs. Independent Repair Shops" examined the parts and labor costs for 10 common vehicle repair jobs on domestic and foreign nameplate vehicles in six cities, including Boston, Newark, Atlanta, St. Louis, Los Angeles and Seattle.

The study was commissioned by AAIA and conducted by Lang Marketing to produce evidence in support of the Motor Vehicle Owners' Right to Repair Act, which the AAIA supports.

"We decided to just get down into the nuts and bolts of the market and see what we came up with," says Ron Rossi, AAIA's director of market research. "Right to Repair was really the impetus to get this thing going. A lot of people were asking us what the quantitative difference was between an independent and dealer repair, so we decided to figure it out."

The survey was conducted in November and December 2008. Researchers conducted 840 telephone interviews with new car dealership and independent repair shop personnel, asking for price estimates replace or repair 10 vehicle components: AC compressors, alternators (rebuilt), drive belts, electric fuel pumps, front brake pads & rotors, radiator, starters (rebuilt) transmission flush and transmission filter replacement, upper ball joints (both sides) and water pumps.

Surveyors inquired about one repair job from each shop contacted. "The person at the shop would basically think that a customer was calling in who was shopping prices, so the process was fairly open in that respect," Rossi says. "I think we got some honest, reasonable responses on both sides."

"The vehicles and produces we selected we felt gave us a good representation between parts and labor," Rossi adds. "We didn't get into repairs like oil changes or air filters that are really more product oriented."

Costs varied wildly between domestic and import models and from city to city. Customers in Los Angeles pay as much as 46.8 percent more at dealerships than at independent shops. Boston had the lowest difference, 19.7 percent, while Atlanta nearly matched L.A. with a 46.6 percent price difference.

Foreign nameplate dealers averaged 36.8 percent higher costs compared to independents, versus 31.5 percent higher for domestic vehicles.

Across both categories of vehicles, the biggest price difference was for radiator replacement, which was 87.4 percent higher at a dealership, followed by water pumps (50.5 percent), starters (41.5 percent) and front brake pads and rotors (40.4 percent).

The average cost for radiator repair for a foreign nameplate vehicle including parts and labor is $325.99 higher at a dealer than an independent shop. The cost to purchase and install front brake pads on a foreign vehicle is $138.92 more at a dealership.

"What struck me overall was that independent aftermarket manufacturers are doing a good job of holding parts prices down to a competitive level," Rossi says. "But they have no control over labor. I think the labor variations were greater than the price variations."

There seems to be no clear pattern as to what factors are driving the price difference. In some cases the price increase was split between parts and labor; in others, either price or labor was significantly higher at the dealerships versus the independent shops. In some categories and cities, independent shops charged substantially more for parts than the dealerships, but only for certain repairs.

In Boston, for instance, independent shops charged an average of $607.50 in parts and $193.13 in labor for a new AC compressor, compared to $385 in parts and $262.67 in labor at the new car dealership (domestic nameplate). In Atlanta, the parts prices were almost identical. In St. Louis, dealerships charged $542.67 for the parts (compared to $421 for independents) and $269.83 for labor (compared to $196.50 for independents).

The report does not delve into exactly why repairs are so much more expensive at dealerships, but Rossi thinks that dealers have been able to charge more because they are perceived as having greater expertise.

"There is a general thought that car dealers are more expensive because their mechanics have a high level of training," Rossi says. "But that goes right back to the Right of Repair issue. One of the reasons for that is access to the repair information, and that's why the legislation is so important."

The Right to Repair bill was reintroduced in 111th Congress in April by Reps. Edolphus Towns (D-N.Y.), Anna Eshoo (D-Calif.) and George Miller (D-Calif.) as H.R. 2057.  Supporters of the bill claim that the increased computerization of vehicles has allowed car companies to block repair information access by owners and independent repair shops.

Rossi says the biggest surprise related to the report so far has been the lack of response from the dealer community. "We didn't get any backlash on this report," he says. "There were no car dealers or other organizations calling and asking what this was all about, or questioning how we could do this. We didn't get any of that."

Response from the aftermarket has been positive, and copies of the report were distributed at the AAIA's legislative summit in March.