July 1997
GM releases the first performance-based specifications for refinish paints by a U.S. auto manufacturer
Starting this year, it is a new ball game for refinish work under warranty at GM dealerships and sublet shops. General Motors has released the results of a three-year project which establishes a standard for refinish paint systems. Now paint systems must meet the GM4901M Specification for repairs and refinishing on GM vehicles under warranty, or the shop may be denied payment (back-charged) for the work.GM4901M is the first specification of its type by a U.S. auto manufacturer for refinish paints. The program was initiated by General Motors Service Technology Group (STG) in cooperation with North American Operations (NAO) paint engineering, which oversees the OE paint process at the assembly plants. Test costs are estimated at about $250,000 for each paint manufacturer, and with the thousands of hours involved, total costs are well over a million dollars.ABRN contacted Brian Dotterer, senior project engineer of GM's Center for Paint Expertise, who was the visionary for this program. Dotterer says "CPE's job is to help ensure the quality of repairs for GM customers. Customer satisfaction is important and customer expectations are higher than ever before. Another reason for performance testing of refinish paint is that GM paint warranties are longer, up to four years with Aurora and other makes, and we want warranty repairs to match the performance of factory paint."One motive for testing refinish paints now is that environmental regulations have caused so many changes in the refinish industry, from major changes in the chemistry to new equipment and new application processes. GM wanted to increase its comfort level with the new paint systems and ensure quality paints were going to be applied to vehicles they warranted."The program has created a number of benefits for the refinish industry. One example is the creation of a level playing field for all major paint manufacturers. This enabled the products of companies whose presence is smaller in the U.S. to be fairly tested against the larger players. Another benefit was to help provide relief to body shops which have had to listen to performance claims by many paint reps. The GM study has taken a lot of the guesswork out of this important decision; now body shops have objective data on which to base their choice of a paint system."A booklet entitled GM Approved Refinish Materials lists each paint system approved under the new GM4901M Specification, from anti-corrosion primer and undercoat primer, surfacer or sealer to the basecoat and clearcoat. In addition, the booklet notes which components of each paint system meet the National Rule, Rule 45 or Rule 1151, so that body shops know which system can be used in their region.Warranty WorkBody shops which do warranty paint or body repairs on General Motors vehicles must use one of the approved paint systems; otherwise, they may be denied payment for the work. More specifically, the GM-approved refinish materials must be used on all GM makes which are repaired under warranty in North America, including Canada. The approved refinish materials are basecoat/clearcoat paint systems (all GM cars and light trucks produced today have basecoat/ clearcoat paint).For most GM dealership body shops and sublets, any change will be relatively minor, because nearly all major paint manufacturers have at least one approved paint system, generally their top-line system. Therefore, most body shops will only have to use the top-line product already delivered by their current paint supplier. Many shops already use the top-line systems, and for those shops the only change will be documentation when necessary.One fundamental change which might not be obvious at first is that only systems are approved, not materials alone. For example, a system typically specifies a particular anti-corrosion primer, followed by a particular sealer, basecoat and clearcoat. Mixing and matching is not allowed with the products. Hopefully, this will go a long way toward convincing painters that to get maximum performance from refinish paints today, it is necessary to know which material is designed to be used over another.The requirement to use approved systems has been in place through all of 1997, but non-complaint shops had until April 15 to switch to approved systems for warranty work.Value for Other Body Shops
For the first time, body shops have objective information about the performance of the major paint systems. Until now, the main source of comparative information on paint systems was through the local paint rep. Now shops can see if the paint system passed the General Motors tests, and soon shops will also be able to see if it passed the performance tests set by Ford.The list of approved materials is also of interest if your shop is hoping for warranty work in the future. It is prudent to learn now which systems are approved, and to be in a position to provide one of them.Even if your shop isn't expecting warranty work, the GM standard can be valuable in improving your product. For example, before the GM program, van converters had to rely on hearsay as to what paint would hold up and best match the durability of OE paint.Another benefit for body shops may be realized by the process of testing and reviewing paint systems: paint manufacturers may begin to streamline their paint system offerings and thereby simplify life for painters.The marketing value of the GM program to all shops should not be overlooked. A common customer concern is whether the new paint is as good as the factory paint. Letting customers know that the paint system you use has been tested and approved by General Motors for use on their vehicles is a very strong endorsement--and a powerful sales tool.What This Means for Consumers
Any refinish work done on vehicles under warranty will be done with materials which have been objectively tested and found to perform to levels specified by GM. Now consumers have measurable standards for refinish materials used on GM vehicles in North America. The approved materials apply only to warranty repairs, but the message is there for GM dealers and sublets: Use approved materials to assure quality and satisfy the customer. The goal is to have refinish work last as long as the best OE finishes.Direction for Paint Improvements
GM's choice of certain paint parameters--such as adhesion or chip resistance--lets refinish paint manufacturers know what the company considers most important. This helps set a direction for research and development. In addition, the measurement of paint performance helps set the bar. In other words, once it is known what the paint is achieving, future performance can be measured and compared to that first measured level. As changes are made in refinish materials, the effects of those changes can be measured to make certain there are performance gains, not losses, in vital areas.Finding the current performance level also helps to determine where improvement is needed--in effect, raising the bar. For example, it was found that the chip resistance of refinish paints was an area where performance was not as good as desired. Further development of catalyzed basecoats is the direction for better performance in that paint parameter. Now that this area is spotlighted and measured, the level at which GM wants to see the chip resistance of refinish paint can be identified.What Is Not Covered
The approved refinish materials did not include reducers, wax and grease removers, tack rags or other related components. The first phase applied only to the core chemistry of the refinish materials. One reason for this was to help make the booklet easy to read and use, so that painters can focus on the core chemistry.The approved systems were designed for use on rigid panels, including SMC and other rigid plastics, and were not specified for flexible parts such as bumpers and fascia. Also, the requirements do not go so far as to certify painters, shop equipment or the body shops themselves.Test Design
Each paint manufacturer was required to supply separate panels of each of four specific colors. The paints were applied over various substrates, including galvanized steel, OE primer and the refinish paint itself. The number of test variables resulted in thousands of painted panels. The refinish paints were applied either by representatives of the paint companies or by specific independent companies.After refinishing, the panels were subjected to seven areas of testing (see sidebar), some of which included multiple tests. For example, weather resistance testing include hazing, fogging, Distinction of Image (DOI), and two years of Florida exposure, which is ongoing. Whenever possible, OE parameters were utilized. Testing was required to be done in North America by independent test labs or by the paint companies. Before and after laboratory testing, painted panels were visually inspected by Dotterer and NAO personnel.In addition to testing of the paint, valuable information was gained about the tests themselves. For example, accelerated studies of weathering were determined to be insufficient for predicting long-term performance.What's Next?
Phase two of the GM-approved refinish program tests materials used on flexible panels. Dotterer says that adhesion is more an issue than flexibility, in part because today's bumpers and fascia are more rigid than their predecessors. Particular attention will be directed toward adhesion on substrates such as TPO, which is now the driving material for fascias at GM. Approval of refinish materials for GM warranty work on a global basis is also planned.The program encompasses ongoing work, too. If a manufacturer changes the chemistry of a previously approved paint system, the system must be retested. GM reserves the right to "DNA" (chemical) testing of any of the approved systems to make sure there are no differences between the approved materials and what is delivered to body shops. In addition, entirely new systems or improved systems can be submitted for approval on a yearly basis. Second-year approvals will be released this fall.Ford Has A Similar Idea
Ford has long been committed to performance testing of refinish paint systems, and has completed the qualifying phase of testing refinish paint systems against exactly the same specifications as its OE-applied finishes. By taking this approach, Ford is accomplishing the first benchmark comparison of refinish paints to OEM paints.Ford's test methodology differs in several ways from GM's. Paint manufacturers were asked to select their most robust system for use on rigid plastics and steel. These paints were then put through a qualifying battery of 10 tests selected from Ford's OE paint tests. Ford obtained the paint materials off the shelf from jobbers, and had representatives from the paint companies prep and spray the test panels. The qualifying tests were performed at Ford using the same procedures, personnel and laboratory as are used for their OE paint testing. The final phase of the certification will subject the qualifying refinish paints to all remaining OE paint tests.The effect of the new refinish paint specifications is not dramatic in the sense that shops will have to buy all new equipment or radically change the way they do things. However, it represents a profound change for the refinish industry, and is part of a major trend which will touch us all. No longer is it "anything goes" as long as the customer will accept it. And no longer are opinions a good-enough basis for choices in materials or procedures as the industry moves toward objective, measurable performance standards.
