It's in the Math: The Lemon Vehicle, A Statistical Certainty

During the past four years, approximately 60,000,000 cars were sold in the United States. “That is a lot of iron, Bubba.” Conservatively 1% of them are lemons. Realistically, 5% is probably closer to the real number of lemons on the road. Some studies suggest that this percentage is much higher.

In one of the earlier incarnations, I taught Statistical Process Control (SPC) and Total Quality management (TQM) to numerous manufacturing companies around southern California. SPC is a set of statistical methods employed to measure and control variation in manufacturing and other business processes. With this background, I feel confident in approaching the numerical reasons why there are so many defective automobiles, RVs, boats and motorcycles on the highways and byways of America. In other articles, I have discussed the financial, social and ethical reasons why there are so many lemons.

Let’s play with some numbers and see if we can understand why your lovely new Ford, Chevy or Mercedes spends more time in the shop than a Russian refrigerator. One percent of 60,000,000 cars equal 600,000 lemons. Remember, most states generally define lemons as a vehicle with a warranty that has not been repaired after a specified number of repair attempts. This is not exact but sufficient to the point of the article. If we thought the 1% was actually 5%, then that would be 5,000,000 lemons on the road. So what is the point here? Regardless of the percentage of lemons determined to be on the road by the various studies, there’s an awful lot of them.

At the heart of this tale of woe is one word, and that word is, variation. If you manufacture anything, variation, excess variation, variation outside of specifications, is the enemy. If you have a process to assemble things, there can be no errors or variations in the process.

These days the Holy Grail of manufacturing is 6 σ (6 sigma). It’s a statistical measure. Essentially it means that if one produces 1,000,000 of the same thing, of the same parts, only 3.4 will be defective. Many companies assert that they are 6 σ companies, that their parts and process meet the 6 σ standard. With the exception of certain computer chip makers, this is just so much bad smelling lawn supplement.

Forget for a moment that the average modern automobile has between 10-15 thousand components. Just apply the 6 σ standard to the number of vehicles made in the last four years. At 3.4 defects per million times 60 (60 million is the number of vehicles sold in the U.S. in the last four years), we would have a total of 204 defects in 60,000,000 vehicles.

Here! Get up from there! Stop rolling around on the floor giggling. It isn’t dignified. It’s ok if you roll your eyes in total disbelief.

Of the 10-15 thousand parts in the modern automobile, some significant percentage of them are connected to one or more other parts, which then form an assembly of parts – some moving and some stationary – that have a common purpose. Examples of such assemblies are the engine, the suspension system, the transmission/differential; the list goes on. What happens if you bolt, weld, electrically connect two or more parts, which were not manufactured to proper specifications. How far out of specification is the entire assembly?

Here’s an interesting equation:

60M X 13K X 6 X N = Lemons Galore

60 million vehicles X 10-15 thousand parts per vehicle X each part has at least 3 dimensions (most have many more than 3 dimensions), all of which may vary X 10,000s of babied and cosseted union employees.

If you have purchased a car with a defect and are frustrated by needing to repair it on a regular basis, you may be able to make a claim through the California Lemon Law. Our California Lemon Law attorneys at Norman Taylor & Associates have an extensive history of successful suits, and have recovered more than $120 million for clients to help them get a new, trustworthy, and safe car.

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