Allison Transmission Models Explained

Allison Transmissions have been around for more than a century, with incredible advancements and innovations in the last 30 years. They’re some of the most durable, long-lasting transmissions in the world, and can be repaired and rebuilt several times without needing replacement. 

Allison Transmissions have been upgraded and improved upon for decades. Learn more about these different series.

Allison Transmission Models

Allison transmissions are the only fully automatic models on the market. Through the years, Allison has updated and upgraded their technology, which they call “Generations”. This can make it a bit confusing when trying to find parts.

Pro Tip: When finding parts for your Allison Transmission, make sure you know what generation your transmission is.

Allison Generation 5

In 2012 Allison upgraded to the Generation 5 model, which is still in use today. The 1000/2000 series made the switch first, and then the 3000/4000 series followed. Differences:

  • This series focuses on prognostics, constantly monitoring operating parameters and notifying the driver if there’s an issue. This includes oil and filter monitoring, and transmission health monitoring. The shift selectors were also re-designed.

Allison Generation 4

These transmissions started to appear in trucks in the early 2000s, around 2004/5 time frame. Difference included:

  • More sensors, more diagnostic capabilities, and advanced configurations of the Allison Transmission product line.

Allison Generation 3

In1998, the Allison Generation 3 replaced the original WTEC II transmission controls. Theis generation ushered in the computer-based diagnostic era, which meant you could use a variety of diagnostic tools to connect to the Allison Transmissions to read codes, clear codes, perform diagnostic commands, and more. Other differences:

  • The controls for the Allison Transmission were updated, offering several different styles.

Allison WTEC

The oldest Allison Transmission configuration was the WTEC. If your commercial truck, RV, or machine is from before 1998, it probably has a WTEC II transmission. This series had no diagnostic software or computer, but you could retrieve codes from the shift selector.

Popular For a Reason

Allison is the world’s largest manufacturer of fully automatic transmissions and hybrid propulsion systems for commercial-grade vehicles. These transmissions can be found at work in a wide variety of applications, from mining and school buses.

Contact Us to learn more about rebuilt Allison transmissions or to find a part for your series.