Diesel vs. Gas
If you live anywhere
near an agricultural center, or a major cross-country highway, you’ve
seen the separate sections of filling stations that cater to
diesel-fueled vehicles, as well as the lines of hissing semi-trucks with
the odd German-import car thrown in. But diesel isn’t just for
semi-trucks and busses, and as for being cheaper – well – that depends.
Advantages of Diesel
Zippy German sports
cars aside, the main use of diesel engines is for trucks that haul or
tow cargo. Why? Well there are several reasons:
- Less maintenance.
Diesel engines have no ignition system, which means fewer tune-ups.
They also use glow plugs rather than spark plugs. Like gasoline
engines, oil changes are required and should take place at
3,000-mile intervals, and filters (air and fuel) should be replaced
- Better torque.
Diesel engines are used in trucks and busses for a reason. They
provide greater torque which means more towing power. Diesel
engines, in fact, are specifically designed as long-stroke engines,
just to create greater torque. They do sacrifice speed, but you
wouldn’t tow cargo with a Porsche, anyway – you’d do it with your
- Longer Life.
Modern diesel cars are lasting in excess of 250,000 miles, and when
used under identical conditions as gasoline-powered trucks, diesel
trucks last twice as long. If you habitually keep trucks past the
100,000-mile mark you’ll find that it’s much less expensive to
rebuild a diesel engine.
- Fuel Efficiency.
The 2.0 liter gas-engine version of the
New Beetle, for example, gets an estimated 31 mpg on the
highway, while the TDI diesel version gets a substantially greater
So, with all these
reasons why diesel is better, should we all be rushing out to buy
diesel-powered trucks? Not necessarily.
One of the greatest
disadvantages of diesel is that vehicles with diesel engines cost more
up front. The 2001 model of the New Beetle we mentioned before came with
an MSRP of $15,900 with a 150 hp 2.5 liter gas engine, while the 1.9
liter TDI diesel version offered only 90 horsepower and cost $2,000
more. In trucks, the price difference is even larger – the same model
Chevrolet Silverado truck was $4800 more expensive when equipped
with a Duramax diesel engine.
What do those numbers
mean? Put simply, it means that it’s the longevity of a diesel-powered
truck that makes it worth while. Despite the fact that the diesel Beetle
has a substantially higher estimated mpg, the reality is that over the
six to ten years the average person uses a normal car, they’re unlikely
to use enough fuel for that difference in mileage to offset the initial
price of the car. To break even, the diesel car would have to “spot” the
other car 50,000 miles.
If, on the other hand,
you plan to keep a diesel truck longer than the average, you may get to
the point where you’ll save money. A properly cared-for diesel engine is
only about half way through its life-span at 175,000 miles, after all.
economy isn’t the only factor you have to consider in the final cost
analysis of diesel vs. gas. For example, while diesel engines generally
require less maintenance, when you DO have to send one to the shop, you
should be prepared to spend about $20/hour more for the work than you
would for a vehicle with a gas engine. Additionally, even the fuel
economy improvement isn’t guaranteed. Remember, diesels are built
for strength, not speed.
The final verdict?
Definitely consider diesel if you’re doing a lot of heavy towing or
hauling, because you’ll need the power, and if you’re the type to keep a
truck forever, but if you’re a truck enthusiast who does most driving on
regular roads, gasoline may be your best bet.