30 Years After Oldsmobile, Is It Time for Diesel Cars?


The Cutlass Ciera, despite being Oldsmobile’s most popular model, still took a huge sales hit when offered with underpowered and poorly designed diesel engines.

Automakers must produce fleets that have a so-called Corporate Average Fuel Economy of about 42 miles per gallon by 2020 and 54.5 mpg by 2025. So far, they are on track to meet those targets with the introduction of new technology over the next few years. These cars aren’t just little compacts hatchbacks, but also pickup trucks, like the Ford F-150 and the Ram 1500.

Automakers have proven that they are up to the challenge of making fuel efficient cars, and creating internal combustion engines that are more and more efficient. But what if there was a way to make the internal combustion engine even more efficient?

The answer lies not in new technology, but something actually very old. In the 1890s, a man named Rudolph Diesel invented an internal combustion engine. Unlike most internal combustion engines, though, Diesel’s was missing a key component. Spark.

In a gasoline engine, fuel is drawn into the cylinders and then ignited by an electrical spark, causing an explosion that pushes the piston down. In a diesel engine, air is drawn into the cylinder, compressed by the piston, and a little bit of fuel is injected, igniting the compressed air, which is quite hot.

As a result, the diesel engine is much more efficient than a gasoline engine, simply because it provides maximum power with a leaner fuel to air ratio, and because diesel fuel is more energy-rich than gasoline when measured by volume. Diesel engines also emit much less CO2 than conventional gasoline engines.  

Why aren’t diesel cars popular in the United States, then? Especially considering concern over emissions and fuel prices, it makes sense that the technology would be adopted for cars, especially when the United States was the world pioneer of the high-torque diesel engine in commercial trucking?

Despite being a big fan of domestic brands and the Big Three, I have to reluctantly admit that they really blew it. During the oil crisis, General Motors was the first to release cars with diesel engines, which they did in their Buick and Chevrolet lines. The LF9, LF7, LT7, LT6, and LS2 were all developed for the Oldsmobile line, and manufactured between 1978 and 1985.

And let me just say, the diesels were not well received. The diesels were put into almost every popular model coming from GM. They were highly anticipated and widely bought. At first. Sales peaked in 1981, and promptly declined. Buyers began complaining of water and foreign material being burned in their engines and their cars spewing black and grey smoke.

The diesel engines used the same head bolts as gasoline engines, which was a problem for the high compression diesel, as the bolts would break and allow coolant to leak into the cylinders and cause hydrolock, damaging the engine. The fuel systems also didn’t come with water separators, causing corrosion in the fuel injectors. Some drivers added anhydrous alcohol to their fuel, which chemically bonded water to fuel, but also ate up the fuel pump seals.

The Oldsmobile diesels were also very underwhelming. With 0-60 times comparable to old farm trucks, very little horsepower, and only 220 lb-ft of torque in the V8, the only fun part of driving an Olds diesel was that it came with a 8-track deck.

So, despite my affinity for the Big Three, I have to admit that they really messed up the “diesel experiment” in the United States. And not only did they churn out terrible engines, but they in effect ruined the diesel market in the U.S. for the next 30 years by planting the image of diesel cars as ugly, inefficient, and unreliable in the public image.

However, things are looking up for the diesel engine. Ford and GM both offer diesel engines in trucks and vans, including their in house engines, the Duramax and Powerstroke, and also offer some vehicles with diesels made by third party specialists, such as Cummins and Detroit Diesel. Fiat-Chrysler doesn’t currently offer diesels for any domestic cars, but Fiats sold in Europe are offered with diesel engines.

As fuel economy regulations loom closer, and as consumers demand vehicles with more miles to the gallon, the diesel engine becomes a increasingly attractive choice for usage in cars. I’m personally hoping that the Big Three will lead the charge in introducing an efficient and economical technology into cars, and repairing the public relations damage that the Olds diesels caused.