The History of the Eight Disciplines Problem Solving (8D)

One popular approach to problem solving is the eight disciplines problem solving, or 8D for short (even though they are now 9D). This is an alternative to the Toyota Practical Problem Solving. I slightly prefer the Toyota approach over the 8D approach developed by Ford, but the 8D also has its advantages. Since it focuses more on urgent quality issues, it has a bigger emphasis on quick reaction and containment plans, but in my view falls a bit short on the Check and Act of the PDCA. I will talk more about the 8D in my next post. But first let’s look at the history of the 8D problem solving, starting with the infamous Ford Pinto fuel tank issue…

The Ford Pinto

The history of the 8D report started—kind of—with the Ford Pinto. Or, to be more precise, with the flawed design of the fuel tank of the Ford Pinto. The fuel tank was placed between the rear axle and the rear bumper.

The Ford Pinto was a subcompact car produced by Ford between 1970 and 1980. It was the first subcompact car by Ford, in response to the popularity of small European and Japanese cars in America. Sales started in September 1970. The car was very popular, selling over 3 million vehicles in total.

The Ford Pinto Fuel Tank Design Flaw

However, the car had one major flaw related to its fuel tank. The fuel tank was located between the rear bumper and the rear axle with the differential. A rear impact, even at slow speeds of 20 miles per hour (30 km/h) would lead to a rupture of the fuel tank. The rear bumper was more cosmetic and offered no protection. The impact pushed the fuel tank into numerous bolts and other sharp edges from the suspension system installation and the differential gear. The fuel tube was also likely to pull out of the gas tank. Gas was likely to spill.

As a result, even a smaller rear-end impact lead to gasoline leaking out of the tank. In some accidents, the gasoline caught fire, for example due to the hot exhaust nearby, as well as other sparks. The body of the car also apparently had some openings in the rear, through which both fuel and fire could enter the passenger cabin. And, fire inside of the passenger cabin is not something anybody wants to experience. Unfortunately, there was also a likelihood that the impact jammed the door, making it more difficult to escape the burning car.

As a result, people died, quite horribly, by burning to death after a relatively small rear-end impact. The number of people who died due to this design flaw is disputed. Some sources claim that there were 27 deaths, while others estimated 500 to 900 deaths.

Also, while the design was flawed, such designs and similar flaws were common for many subcompact car makers at that time. Automotive safety testing was still in its infancy, and only front impacts were considered. A rear impact test standard was still in development while the Pinto was also under development. The standard aimed for a 20 mph rear impact with a movable barrier (which gives way), later changed to a fixed barrier (which does NOT give way), and later increased to 30 mph. Ford voluntarily started to use the moving barrier 20 mph standard in 1973, but objected to the more stringent standards (like many other car makers).

Cost-Benefit Analysis

To understand the impaction the problem, Ford did what was also common at that time, a cost-benefit analysis. They tried to calculate the cost of changing the design and doing a recall in comparison to the cost of people burning to death. They estimated that it would cost around $11 per car ($80 in 2025 after inflation) to reduce the risk of fire for 12.5 million cars and trucks across all manufacturers, or $137 million in total ($1 billion in 2025). Cheaper solutions were also considered, costing as little as $1 ($7 in 2025) for a rubber bladder or plastic gadget. The Grimshaw v. Ford Motor Co. lawsuit at a later point listed the following possible improvements and their cost:

• Longitudinal side members: $2.40 ea.
• Cross members: $1.80 ea.
• Shock absorbing “flak suit” for the fuel tank: $4.00
• Tank within a tank and placement of the tank over the rear axle: $5.08 to $5.79
• Nylon bladder within the tank: $5.25 to $8.00
• Placement of the tank over the rear axle with a protective barrier: $9.95
• Substitution of rear axle with a smooth differential housing: $2.10
• Protective shield between differential housing and fuel tank: $2.35
• Improvement and reinforcement of rear bumper: $2.60
• Additional 8 inches (200 mm) crush space: $6.40

They compared their initial estimate of the fix with the cost of the lawsuits and the damages to be paid. They estimated that the solution would prevent around 180 burn deaths and another 180 serious injuries per year, and a total of 2100 destroyed cars (again across all manufacturers and models, not just the Forst Pinto). In 1973, they estimated a cost of $200 000 per burn death (a figure provided by the National Highway Traffic Safety Administration [NHTSA] to Ford and other automakers for regulatory purposes, $1.4 million in 2025), $67 000 per burn injury ($ 500 000 in 2025), and $700 per car ($5000 in 2025), for a total of around $50 million ($360 million in2025).

Obviously, 137 million is more than 50 million, so the decision was made to let them burn as the more cost-effective solution. This internal controversial memo is often referred to as the “Pinto Memo.” However, the general public did not agree with this decision. Not at all! In any case, Ford decided not to act.

Public Outcry and Lawsuits

A 1972 lawsuit Grimshaw v. Ford Motor Co. for such a Ford Pinto fire awarded multiple hundreds of million dollar of damages, much more than what the fix would have cost for all cars of all makers. The Mother Jones magazine published a damming article “Pinto Madness” in 1977, calling the Pinto a “firetrap.” The following public outcry forced the previously reluctant National Highway Traffic Safety Administration (NHTSA) to start an investigation, concluding that

1971–1976 Ford Pintos have experienced moderate speed, rear-end collisions that have resulted in fuel tank damage, fuel leakage, and fire occurrences that have resulted in fatalities and non-fatal burn injuries ... The fuel tank design and structural characteristics of the 1975–1976 Mercury Bobcat which render it identical to contemporary Pinto vehicles, also render it subject to like consequences in rear-impact collisions.

To make up for their previous hesitation, the NHTSA now tested the Pinto with a lot of vigor, using test settings that were much more demanding than what was common at that time. One NTHSA engineer said on the much more stringent tests that “Just because your friends get away with shoplifting, doesn’t mean you should get away with it too.”

In 1978, the NHTSA ordered a recall of 1.5 million cars, the largest automotive recall up to then. (Side note: Current record holder is the 2014 Takata Airbag recall with over 67 million vehicles recalled in the USA, and over 100 million worldwide.) Overall, it was a public relations disaster for Ford, and also much MUCH more expensive than their initial cost-benefit analysis suggested. Some called this a landmark case for making large corporations accountable.

Development of the Team Oriented Problem Solving (TOPS)

Neglecting quality cost Ford dearly, both financially and in their reputation. This was one of the reasons for Ford to develop a structured problem-solving approach to prevent these issues. As a military supplier they were probably heavily influenced by the MIL-STD-1520C military standard for corrective action and disposition system for nonconforming material. This standard also aims to identify quality problems and their root causes, using teamwork to prevent these issues in the future.

The results of this work, the Team Oriented Problem Solving Manual by Ford was first published in 1987. In the 1990s this evolved to the now well known 8D, with a ninth D, D0 or D-Zero for emergency responses added later, as well as the concept of escape points to understand why the problem was not detected earlier. The full list of the 8D (9D) is:

• D0: Preparation and Emergency Response Actions
• D1: Establish a Team
• D2: Describe the Problem
• D3: Develop Interim Containment Plan
• D4: Root Cause Analysis and Escape Points
• D5: Develop Permanent Solution
• D6: Implement Permanent Solution
• D7: Prevent Recurrence
• D8: Close Problem and Recognize Contributors

Note that there are many variations and rephrasings of this list from different sources. This 8D problem solving methodology is now widely used in industry, especially for quality problems. Let me show you in my next posts more on the Eight Disciplines Problem Solving. Now, go out, solve your quality issues before your customer suffers from then, and organize your industry!