March 2013 Archives - Transmission Digest
6 Steps to Getting Your Big BUT Back in Line

Most people allow their environment to direct their actions. If you work for a boss who is not interested in your new ideas, you stop creating new ideas. If your coworker avoids teamwork, you retreat to your cubicle. If your spouse fails to uphold his/her end of the bargain, you stop trying.

Are We Listening?

I heard a report recently on NPR (National Public Radio) that said, “Doctors are not good listeners; that is why a lot of unnecessary tests are done.”

When I heard that I said to myself, “That is true in our field too.” If we don’t listen well to the patient we may misdiagnose. Let me tell you about something that happened to me just recently that emphasizes this point. We had a customer sent to us by a local general-repair shop. He was a student here for the winter break visiting his family and was about to leave when he started to have transmission problems on his 1998 Mercedes M320.

Magna Powertrain Transfer Cases, Part 3

In this third part of the series on Magna Powertrain transfer cases found in late-model GM trucks, we look at MP3023/3024 (RPO code NQH). These units are known as ATC, or automatic transfer cases, which are computer activated and have five modes: Auto 4WD, 4HI, 4LO, 2HI and Neutral.

Don’t Overlook the Flex Plate

In the early 2000s, I was working as a transmission technician for a Dodge dealership in Omaha. I had been working there around five years. A customer brought in a 1998 Dodge Caravan equipped with a 3.0-liter V-6 and a 41TE (604) transmission. The customer complained that the vehicle had no power. He thought it was a transmission issue, so the Caravan was routed to me for diagnosis.

March 2013 Issue

In This Issue
Nissan/Infiniti RE5R05A: Gear-ratio-error codes and/or TCM-incompatibility codes
Nissan/Infiniti RE5R05A: Compatibility of turbine shaft, pump stator and torque converter

The 4R100 with a Mysterious No 3-4 Shift

A friend of mine who owns a local transmission shop called me recently to see whether I could help with a difficult problem he was having with a transmission. He had taken in a Ford truck with a 4R100 transmission that had no fourth gear. The fluid was badly burnt and there was a lot of clutch material in the pan.

Serviceability Report: Audi A6

Serviceability Report: Audi A6

Tech to Tech

Subject: Serviceability report
Vehicle Application: 2012 Audi A6 Quattro 3.0-liter
Essential Reading: Diagnostician, R & R
Author: Craig Van Batenburg

Do the German-model engineers care about their technicians?

Salvaging Late-Model 4L80-E Stators

As if having another wave of cracking pistons was not bad enough, the problems with the second-generation stators were even worse. The first issue rebuilders noticed was excessive wear in the stator housing where the roller-clutch inner race contacts the housing. On some converters, the inner race would wear its way out through the stator housing and into the impeller hub. This was especially problematic because – unlike in the first generation – the impeller side of the stator was not a removable stator cap.

Fearful Leadership: Do You Suffer from It?

It’s a tough time to be a leader. What with the economy being so unforgiving, making smart business decisions is crucial. That’s true in terms of not only strategy (whether to change your service mix or move into a new marketplace) but also relationships (whether to fire the high-volume performer who drives you nuts or address the conflict head-on). All actions have consequences. So does lack of action. And with the margin for error so slim, you want to make sure you’re thinking as coolly and clearly as possible.

Valve-Body Bore Preparation

We’ve all been there. You get your bench set up to clean and inspect the valve body, pull the first retaining clip – and then it happens. The first bore you touch ends up having either a stuck end plug, valve, sleeve or – worse yet – all the above. Fast-forward a few steps and, what the heck, how did that O-ring get torn? Why do I always end up with sticking valves on the way back together?

The thing to keep in mind is that most valve bodies use aluminum castings that can dent, scratch and develop ridges very easily. Once this occurs, it can quickly lead to damaged components and lost time trying to repair them. The best place to start in avoiding this scenario is to understand why it happens.


The ASM Handbook on Fatigue and Fracture (Figure 1) defines fretting as: “A special wear process that occurs at the contact area between two materials under load and subject to minute relative motion by vibration or some other force.”

Fretting wear is usually associated with electrical contacts rather than non-electrical things, but fretting and fretting wear occur with both.