Vehicle Maker Recommendations

Figure 3. There are different strengths of steel but no laser welds along the length of the Dodge Caliber B-pillar.

Today there are more vehicle maker recommendations for partial replacement than ever before. Partial replacement recommendations may include sectioning or replacing a portion of a part at a factory seam. I-CAR has always recommended following vehicle maker recommendations when they exist; that has not changed.

What has changed is the number of procedures and service parts that are available. When a partial replacement recommendation is available from the vehicle maker, the options for replacement include partial or complete replacement.

 One question that is often asked is “if there is a procedure available, but there is a kink behind the recommended sectioning location, can general sectioning guidelines be used?” Generally speaking, the answer should be “no.”

The procedures published by the vehicle maker are tested and approved for the repair of that vehicle. That location represents the area that the design engineer has deemed the best place to do the procedure. One could conclude that areas without recommendations for sectioning don’t fit the criteria established by that design engineer. Some vehicle makers, Volvo for example, have multiple sectioning locations available for a single part. Sectioning in an area behind an approved vehicle maker sectioning location would be a subjective business decision.

Some vehicle makers offer a number of sectioning procedures on a particular vehicle. If the vehicle maker allows sectioning of pillars, rocker panels, and rear rails, but not a front lower rail, you may want to consider why there isn’t a procedure available.

Is there a design reason why the vehicle maker doesn’t offer a procedure for that area? Was testing done that resulted in not recommending a procedure? Unfortunately, the collision repair industry professional does not know the answer to these questions, thus adding more subjectivity to a decision to section without the support of a vehicle maker recommendation.

There are also a number of vehicle makers that have published bulletins that warn against sectioning if no vehicle maker recommendation exists. Honda and Chrysler are two vehicle makers who have published such statements. In fact, Honda has published this statement on multiple  occasions.

Ford Motor Company issued a statement in 2006 recommending that structural repairs only be completed using Ford-recommended repair procedures. Where no factory-supplied information is available, Ford recommends repairs be made at existing joints or seams using repair procedures that duplicate factory assembly processes and techniques.

In an effort to assist the collision repair industry in identifying which vehicles have sectioning procedures available, I-CAR, in association with State Farm and Tech-Cor, developed the partial replacement recommendations matrix. To determine if there is an approved partial replacement procedure available for a particular vehicle:

    1. Visit www.i-car.com/partialreplacement
    2. Enter the vehicle year and make from the pull down list and click the “Find Partial Replacement Recommendations” link.
    3. Enter the model information and click on the “Find Partial Replacement Information” link.
    4. If there are recommended procedures available from the vehicle maker for the front lower rail, pillars, rocker panel, roof rail, rear rail, or trunk floor, the results will indicate its availability. There is also a link to the vehicle maker’s technical information web site on the results page.

Advanced High-Strength Steel
The most significant change in steel vehicle construction in the past 20-plus years is the substantial increase in use of advanced high-strength steels. Many of these steels fall into the high-strength and ultra-high-strength steel categories. Before discussing what the increased use means to sectioning, let’s first take a look at the reason why vehicle makers are using an increased amount of AHSS.

Vehicle makers are tasked with designing vehicles that offer an unprecedented number of creature comforts and electronic safety features. All of the computers and wiring associated with these electronic systems add a significant amount of weight to the vehicle. At the same time, vehicle makers are required to reduce overall vehicle weight, reduce emissions, and improve fuel economy.

Lastly, vehicles are being designed to provide a historically high level of protection against injury and fatalities in a collision. Federal Motor Vehicle Safety Standards and Regulations (FMVSS) requirements are becoming more and more stringent and the vehicle makers are racing to meet the increased safety demands. Vehicle safety and crashworthiness are becoming primary reasons for one vehicle being selected over another by the safety-conscious consumer. All of these factors combined have resulted in the vehicle makers working with steel manufacturers to develop new, lightweight steels.

These new steels have a variety of names and characteristics. One characteristic that many of the AHSS share is their strength and vulnerability to heat. When heat, including welding, is introduced to a sectioning location that is not recommended by the vehicle maker, the integrity of that part may be significantly compromised.

To emphasize the importance of not applying heat unless recommended, I-CAR performed some directional tests on boron-alloyed steel samples. The baseline boron-alloyed steel sample fractured at 4,625 psi. A similar piece that was cut and GMA (MIG) welded fractured at 2,400 psi, a decrease of nearly 52%.