If you are shopping for a new, 2010 car or truck to replace a vehicle that is several years old, you could be in for a surprise when you learn the costs of new car insurance. Protect yourself from the shocking premium before you purchase your new car.

Think body style

New car insurance can vary widely from one body style to another. For example, you may know that sports cars cost more to insure than family sedans. That general rule of thumb doesn’t just apply to traditional sports cars; it also applies to the two-door versions of popular family sedans such as the coupe version of the Honda Accord. That’s because people who drive these cars statistically tend to drive more aggressively than their sedan counterparts, making them a greater risk and causing their insurance rates to rise. Interestingly, convertibles tend to have lower insurance rates than their hardtop counterparts.

Since bigger cars are safer, you might think that larger vehicles, like crossovers and SUVs, are cheaper to insure. This is not always the case. The largest SUVs can inflict more damage on smaller cars in a collision, which means costlier repairs, again leading to higher insurance rates.

Consider the engine and transmission

Like body style, the car’s engine and transmission often can affect the insurance rate. Generally, the greater the horsepower, the higher the cost of new car insurance, even when you are considering the same car with a variety of engines. When it comes to transmissions, cars with manual transmissions are generally more costly to insure than those with automatic transmissions. An exception to this rule is the pickup, which often has a manual transmission because of its use as a work or tow truck. The reason for the higher rates again relates to the typical driver. Those behind the wheel of cars with higher horsepower and manual transmissions tend to drive more aggressively and become involved in more collisions.

Look at the brand

While body style, engine size and transmission type are all major factors in the way that rates are computed for new car insurance, rates can vary for similar, competing vehicles primarily due to their safety ratings and their likelihood of being stolen.

Edmunds.com’s True Cost to Own tool features average insurance rates among other ownership costs over a five-year span for all cars and trucks. Using this data to compare three sets of competing vehicles, I found it revealed insurance rates that varied widely between models.

For example, comparing similarly equipped versions of the 2010 Honda Civic and the 2010 Nissan Altima showed the Civic cost $1,615 less to insure on average over a five-year span. When comparing similarly equipped models of the 2010 Toyota Camry and the 2010 Ford Fusion, there was a difference of $859 in the Fusion’s favor. When comparing the two best-selling pickups, the 2010 Ford F-150 and the 2010 Dodge Ram, both similarly equipped, the F-150 cost $592 less to insure on average over a five-year span.

Once you’ve narrowed your choices, call your insurance agent or use a free online quote service such as Insureme.com and supply the exact details of the makes and models you are considering to obtain insurance quotes before you make your final decision.

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