In This Issue
Chrysler Transmissions: Consistency in Electrical Diagnosis Since 1989
For those select few of you who have taken on the task of either rebuilding or installing a Volkswagen 01M transmission, you know that these units can be difficult. This transmission is very easy to rebuild, and usually the internal parts are in good shape.
2005 is now in the history books, and I hope all of our readers enjoyed the holidays. It is a time-worn habit to make resolutions and try to improve our situations for the new year.
Time is a human creation. All other forms of life and some primitive tribes do not have any understanding of time. They are driven by instinct, seasonal changes and their life cycles, but we are the only species that has created the concept of time. This ability to measure each day precisely and then make future plans is a blessing and, at the same time, the source of tremendous pressure, which is self-induced.
The more training technicians receive and can understand and apply, the more efficient they will be. And that translates to money.
A 1993 Nissan Maxima was brought to a transmission shop. The customer complained about a persistent transmission leak that was leaving a spot on his garage floor and said the transmission had been rebuilt about a year earlier. He added that the vehicle was returned to the original shop within the first month to have the passenger-side axle seal replaced. Since the axle-seal replacement did not eliminate the leak, the vehicle was taken to a general-repair shop, which replaced the axle seal and installed another axle under warranty. The customer said that each time the vehicle was worked on, the leak seemed to stop for about a month, then reappear.
A 604 transmission with a 740 code led to many different approaches and attempts to troubleshoot the underlying problem. As the possible causes were narrowed down, the focus began to turn toward the converter. Replacing the converter with a factory unit eliminated the 740 code, and since the code would show up on any road test, this seemed like the perfect vehicle to identify the root cause.
This transaxle has a bi-directional ratio-control motor (RCM) on top of the valve body (see Figure 1). The RCM indexes with a lever attached to the variable-ratio-control valve in the valve body, as Figure 2 shows. The opposite end of this lever sits inside a pocket of a device called the drive-pulley follower, as shown in Figure 3 from the valve-body case side with the valve body removed.