Fuel Economy Technology Systems: Automatic Transmission

In this series, we look at several methods used to boost fuel economy, different considerations to repair them, and any special precautions the collision repair industry needs to know. Let’s look at transmissions.

Tightening regulations on fuel economy along with rising awareness about pollution have influenced vehicle design and function in recent years. However, most consumers are not willing to sacrifice comfort, vehicle size, of power, so auto makers needed to use different methods to boost the fuel economy numbers. For the most part, aerodynamics can be directly related to fuel efficiently. The smoother air flows over the vehicle, the less power is required to make the vehicle move, leading to higher fuel economy. Unfortunately, a vehicle that has excellent aerodynamics may not be a functional vehicle for every consumer. So, other measures needed to be taken.

Traditional transmissions have two major categories, manual (standard) and automatic. Manual transmissions have the driver change the gears, whereas automatics shift on their own without driver input. Manual transmissions have always been known for their faster acceleration and better fuel economy. Well to much surprise, today's automatic transmission outperforms the manual transmission on almost all fronts. It gets consistently better fuel economy, has faster acceleration, and even smoother shifts than ever before. If that’s not enough, many automatic transmissions can also be manually shifted if you want to reminisce about the good old days every now and then. For this reason, you may have noticed the decline in manual transmissions. With the new high-tech automatics there can be special considerations for repairers.

It is common for most modern automatic transmissions to have 8, 9, or even 10 gears. More gears translate to better fuel economy and smoother shifts. Many automatics don’t even feel like they are shifting because they are so smooth. There is also a different class of automatic transmissions called a continuously variable transmission (CVT). CVTs do not have gears so they never shift. They simply have a belt and pully system that can change the size of the pully to simulate a gear change.

Computers can also be credited with helping the transmission perform at the top of its capabilities. Perfectly timed shifts take away much of the friction that slowed down the old models. However, computers can be sensitive to collisions and disruption in the power supply. It is important to scan, diagnose, and repair if there are transmission problems after a collision. Depending on the vehicle, a calibration or learn procedure may be required after the battery is reconnected.

The main problem with this generation of transmissions is the complexity of them. It can be extremely difficult to service them, and some may not even be able to be serviced. This complexity makes it even more important to reference the OEM repair information. Such a hi-tech system can easily be damaged by incorrect procedures.

Always research repair procedures to make sure that all repairs are being performed according to the manufacturer. If these systems are not properly functioning after a collision, the vehicles fuel economy may be sacrificed, which leads to an unsatisfied customer. Though this system may not pose a safety concern, it can cause a problem with fuel efficiency, emissions, and customer satisfaction.

Additional I-CAR Collision Repair News you may find helpful:

• Fuel Economy Technology Systems

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Article validated in 2026