t first glance, the Isuzu Trooper and Acura SLX look very similar. Upon closer inspection, it is clear these two sport utilities are more than just similar, they're practically identical. Indeed, the only significant differences between the two are variations in trim level, option packages and advertising pitches. They wear different nameplates, yet these two rigs are virtually the same. How can this be?

In the world of platform sharing, where two or more vehicles are built with virtually the same mechanical components, Trooper and SLX are shining examples of "rebadging" - an accepted manufacturing approach that sees the identical vehicle sold under two or more different manufacturer nameplates.

Historically, auto manufacturers have shared platforms between different model lines as a means of controlling manufacturing costs and leveraging investments in costly tooling and assembly processes. And, historically, savvy car shoppers have taken the time to compare shared platform vehicles - in search of the best value.

The payoff could be financial, depending upon price differences or differences in effective rebates. Or the payoff could be psychological, as you learn some of the secrets of the auto business and gain the latitude to be more selective about which dealer to give your business. Instead of bracing yourself to visit a dealer with whom you've previously had a bad experience, you may discover a virtually identical car - with a different nameplate - down the street at a dealer you like. Of course, there may be trade-offs to consider, such as differences in option packages and color schemes, but in the long run an informed shopper does better than an uninformed shopper.

At one end of the spectrum is a form of platform sharing known as "rebadging," outlined above. Rebadged vehicles are highly similar, with only slight cosmetic differences - even though rebadged vehicles may be advertised and marketed quite differently, targeting different types of buyers. At the other end of the spectrum is a type of platform sharing that is more or less undetectable to the average consumer eye, where vehicles with considerably different body styles are built on the same frame with the same engines, transmissions, suspensions, and so on. The new Pontiac Grand Am and Oldsmobile Alero - both of which share the same General Motors platform - are a good example this.

If you're in the market for a new car or truck, and considering any of the vehicles listed in the table below, be sure to check out CarPoint's Web site for the shared-platform competition.