January 2003 Archives - Transmission Digest
The New Breed of Active Transfer Cases – the New Venture Gear 226

The newest design level in the active transfer case is the NVG 226. GM introduced the Trailblazer, Envoy and new Bravada models that feature a newly designed straight six-cylinder engine. This engine has very high horsepower and torque output and is arguably the smoothest-running straight 6 ever produced. In order to complete this almost vibration-free package, GM chose the NVG 226 transfer case.

Necessary Tools

One of the responsibilities of a reputable transmission shop is to prevent problems before they occur. Checking the quality of the parts that are going into the transmission is one way to achieve this. Checking the hardness of the metal parts is an important part of this process.

January 2003 Issue

Issue Summary:

Accumulator springs that have been installed incorrectly, or accumulator-piston shafts that are scored or worn and are interfering with accumulator-piston movement, can cause various shift-quality complaints.

On some 1996 and 1997 Ford Taurus and Sable models, the PCM may have been reprogrammed to eliminate TCC operation during normal driving conditions.

Stuck On, Stuck Off or Just Plain Stuck

With the introduction of OBD-II, a ton of additional codes became available (remember, we were always asking for more information). In some instances, these new codes were a great help because they did not just indicate a short or an open circuit but also pointed to parameters that were out of range, which included both mechanical and electrical problems.

Even Failsafe Is Subject to Change

Since then, technology has leaped forward at a vicious pace, not breaking for breath. And with this technological race among the “Big 3” manufacturers (U.S., Japan and Europe) comes the need for various computer strategies. Failsafe is one of those strategies that has experienced a change.