2005 Auto Brand Quality Ratings and Rankings
by James Bleeker
This page provides two rankings of the brands of automobiles sold in North America
from model year 1997 to 2004. Each ranking employs a different method of computation.
The statistics used in the computations for rating and ranking the brands are those found within the April
2005 issue of Consumer Reports. The two sections providing the necessary statistics are CR's Used-Cars-To-Avoid list and its reliability charts. Reliability is defined by the magazine as the infrequency of serious problems, which it measures annually by a subscriber survey.
The first ranking of the car brands is based on each brand's infrequency of trouble-prone models. This ranking provides a measure of how well each brand's models successfully avoided the bottom end of the model-quality spectrum.
The second ranking of the car brands is based on the average of the overall reliability ratings of each brand's models. The second ranking provides a measure of how well a brand's models performed over the entire model-quality spectrum.
2005 Auto Brand Quality by Infrequency of Trouble-Prone Models
To form a brand-quality measure from the 2005 list of Used Cars To Avoid, the first step is to count each brand's entries on the list. Each model year of each model is treated as a separate entry.
Next, as the number of automobile models sold under a brand name varies greatly from brand to brand, it is necessary to take account of the fact that a brand with more models has a greater opportunity to have more model years of low quality. To compensate for a possibly inflated, or deflated, frequency of trouble-prone model years within a brand, as well as a variability in model data sufficiency, the number of a brand's entries in CR's
2005 Used-Cars-To-Avoid list is divided by the total number of overall reliability ratings for the brand found in the reliability charts of the same issue of Consumer Reports. The overall reliability ratings are found in the
Reliability-Verdict row of the 2005 reliability charts.
By the method of computation, this quality measure begins with 0 and may run to a value some greater than 1. The value of 0 is the highest quality rating attainable by a brand and is achieved only when a brand has no entry on the Used-Cars-To-Avoid list.
The quality ranking of the car brands by the foregoing computations, together with their quality ratings,
is given in the first bar graph below. Only those brands with at least 5 overall CR reliability ratings are included.
2005 Auto Brand Quality by the Average of Overall Reliability Ratings
To compute brand-quality ratings and assemble a brand-quality ranking
using Consumer Reports' overall reliability ratings, a number is associated
with each rating. A +1.0 is ascribed to a rating of Better Than Average, a 0 to a rating of Average,
and a -1.0 to a rating of Worse Than Average. Then an average is taken over all of the brand's model years and models offering an overall reliability rating. CR's
2005 overall reliability ratings are found in the Reliability-Verdict row of its reliability charts
and are limited to three grades - Better Than Average, Average, and Worse
For this measure of quality, the range is from -1.0 (the worst possible) to +1.0 (the best possible).
The quality ranking of the car brands by this set of computations, together with their quality ratings,
is given in the second bar graph below. Only those brands with at least 5 overall CR reliability ratings are included.
The Bar Graphs of 2005 Brand Quality
In both of the graphs that follow, the order of the car brands is with the
best on top.
When two or more brands have no entry in CR's list of Used
Cars To Avoid, the brands are listed in descending order of
number of overall reliability ratings (a brand with a greater
number of overall reliability ratings appears above a brand with
fewer ratings), as those brands with a greater number of ratings
would have a greater opportunity for a trouble-prone model year
to be found.
Summary and Analysis
Some important points given by the above graphs are:
1. By 2005, all three of Ford Motor
Company's North American brands - Ford, Mercury, and Lincoln -
had moved into the top half by both of the above quality
2. In 2005, all four of the Chrysler Group's
brands - Chrysler, Dodge, Jeep, and Plymouth - were in the
bottom half by both quality measures.
3. In 2005, nearly all of General Motors'
North American brands - Cadillac, Oldsmobile, Pontiac,
Chevrolet, and GMC - were in the bottom half by both quality
measures. GM's Saturn brand squeezed into the top half by one
measure, but was in the bottom half by the other. GM's Buick
brand was in the top half by both measures.
4. In 2005, both of Toyota Motor Corporation's brands
- Toyota and Lexus - and Honda Motor Company's Acura were in the
Top 5 by both measures of quality. Honda's Honda brand was in
the Top 5 by one measure and not by the other; the Honda brand
continued to suffer from its rebadging of an Isuzu product as
the Honda Passport, a fill-in until it developed its own SUVs.
To view the graphs showing the 2005 ratings and rankings of the car
manufacturers, click Go.
For a Google Knol that summarizes the changes in auto-brand and auto-manufacturer ranking by these quality measures from 1990 to 2010, click
AutoOnInfo.net: The auto-quality website with the
Open Directory Cool Site Award.