Automatic Transmissions

Fleets should expect to see improved fuel economy from automatic transmissions, which have full power shifts and a torque converter to seamlessly transition between gears. They are most valuable in city driving where a significant amount of shifting is required.

Improved driver recruitment and retention are big factors behind many fleet owners’ decision to specify these transmissions over manual transmissions. In addition, they reduce the variability in fuel economy from one driver to the next.

Although it is too early to predict the payback for automatic transmissions, their business case is expected to be strong over time.

Note: All benefits and consequences are the same for automated manual transmissions (AMTs) and automatic transmissions except for the fuel economy performance.  AMTs offer 1-3% fuel economy improvements and enable even higher levels of performance in future with features such as downspeeding, and the use of GPS to better manage hills and valleys.   Fuel savings from automatic transmissions are yet to be determined.

Benefits

Industry studies show that a driver can affect a truck’s fuel efficiency by 30%. Automatic transmissions take the driver out of the shifting decision-making process and allow technology to determine the proper time to shift gears.

Many driver recruits have no experience operating vehicles with manual transmissions. Specifying trucks with automatic transmissions enlarges the driver pool, which is a key advantage given the current driver shortage. Since these transmissions make the trucks easier to drive, drivers will be less tired at the end of the day, which should help fleets with driver retention.

Since drivers are already familiar with automatic transmissions, driver-training time will be shortened and the driver will be able to start working more quickly.

Automatic transmissions decrease the variability in the fuel economy of trucks or drivers in a fleet, compared to the variability in fleets using manual transmission. Electronically controlled transmissions make poor drivers much better, average drivers better and good drivers slightly better.

Electronically controlled transmissions improve driver safety because they allow the driver to concentrate on the road ahead rather than having to worry about shifting. The driver can keep both hands on the wheel.

Electronically controlled engines, transmissions, and other powertrain components offer the opportunity for improved and fine-tuned performance for various duty cycles and terrains.

Challenges

Automatic transmissions are estimated to cost more than automated manuals, but market cost data is not yet available because the product used in Class 8 applications has not been on the market long enough.

Expectations are that residual values will be on a par with trucks equipped with manual transmissions.

Electronically controlled transmissions have more moving parts and require software to operate. As a result, fleets can expect a small increase in maintenance cost.

To get the most from electronically controlled transmissions, care needs to be taken in the specification of the engine, transmission, axle, tires, and road speed combination of the entire vehicle.

Electronically controlled transmissions

COMMON FLEET STRATEGIES

Fleets are increasingly investing in electronically controlled transmission. Many fleets have said that going forward all of their vehicles will be spec’ed with electronically controlled transmissions.  Fleets have indicated these transmissions improve fuel economy but also help with driver recruitment and retention efforts. Fleet owners believe spec’ing electronically controlled transmissions makes them more attractive to younger drivers who have no experience driving standard transmissions. Learnings from automated manual transmissions show that use of electronically controlled transmissions can be touted in recruitment efforts, and can improve the driving experience.

WHAT OTHERS ARE SAYING

Decision-Making Tools

The study team developed several tools to help fleets in making their decision about electronically controlled transmissions.

  • The Comparison Chart shows features of the various electronically controlled transmissions currently on the market.
  • The Payback Calculator is an incremental analysis tool designed to compare two or more of the situations and/or equipment selections available to a fleet, using the fleet’s own data or their own best estimates.
  • The Confidence Matrix is used to inform fleets of the study team’s confidence in the technology being studied vs. the payback a fleet should expect to receive from the technology.

Manufacturers

CONCLUSIONS

After 25 years of development globally, electronically controlled transmissions are:

  • Are ready for prime time — These transmissions are proving to be reliable and adoption rates validate end user trust in their performance and durability.
  • Offer a good business case for adoption — They deliver fuel savings of 1-3%, have low operating costs and an acceptable initial purchase price.
  • Are an enabler of additional benefits — They allow further improvements in fuel economy, safety and operational efficiency especially as manufacturers combine highly integrated components into effective powertrain combinations.