You may recall that the 4L80-E made its appearance in 1991. And whether it was in two-wheel-drive or four-wheel-drive configuration, the output carrier had the exciter ring for the output-shaft-speed (OSS) sensor pressed onto it.
For many years trainers, myself included, have been teaching our industry owners and managers to do everything we can to keep the mystery in our trade, and to not freely give away our diagnostic and repair secrets to the motoring public and our competitors. Our education is something for which we paid dearly, and we should be compensated for providing it. As much as we would like to keep that information proprietary it’s getting more difficult every day, which is why our sales skills must become sharper.
Traditionally, all motor-vehicle final-drive elements (differentials, or rear ends) have consisted of a ring and pinion, with the ring gear mounted on a differential carrier. The differential carrier contained a set of side gears splined to the drive axles and a set of pinion gears allowing the side gears to rotate at different speeds.
The differential is necessary because the outside wheel on an axle has to cover more distance in a turn than the inside wheel. This means that the outboard wheels must rotate faster than the inboard wheels; hence, the “differential” in wheel speed.
The shift strategy of Chrysler’s 45RFE and 545RFE transmission is clever and unique. The computer controls a total of seven solenoids in the transmission to perform all shift-feel, shift-timing, converter-clutch-apply and failsafe strategies.
Choosing the correct surface finish for bonding can be controversial. Some rebuilders claim you can bond to a surface as smooth as glass, provided the bond-line temperature and the compression pressure are correct. Others claim that a very rough surface finish is needed for a good bond. The finish of a machined surface is rated on a roughness-average (RA) scale.
ZF is one of the world’s leading powertrain manufacturers. One of its divisions, in Saarbrücken, Belgium, specializes in producing automatic transmissions for cars.
When you consider working on a ZF automatic, your starting point should be the tag, which leads you to the information and application required for the unit (see Figure 1).
Replacing parts is the last step in the repair process. The first step should be a methodical diagnosis to isolate the cause of the malfunction. This is not possible unless you understand how the component you are working on is supposed to operate and how it is related to the other systems that make up the modern motor vehicle.
Although some customers will try to get away as cheaply as possible, most realize that they have to at least pay a fair price to get a car fixed properly. Fortunately for us, people who place quality and service above price outnumber those who don’t by four to one. That means that about 80% of your customers are far more motivated by the look and the feel of the service than the price of it.
The Isuzu/GMC Forward Tiltmaster truck (otherwise known as the NPR/W4/4000) with a diesel engine and the JF506E transmission has a setup for recovering engine coolant that has been known to cause hard starting or a no-start condition. And it always seems to become a problem after the transmission needs repair; at least, that is what the customer says until you finally figure out what is the real cause of the problem.
You may be familiar with a transmission called the JF506E, which in the North American market can be found in the VW Jetta, Golf and GTI; the Mazda 6 and MPV; the Jaguar X Type; and the Land Rover Freelander. It is manufactured by Japanese Automatic Transmission Co. (JATCO). In Europe the JF506E is in vehicles such as the VW Golf and Sharan, the Land Rover Freelander, the Jaguar X Type and the Ford Mondeo, to name a few. And the company said something to this effect: “You build the car and we will make this transmission fit it. The transmission will be versatile enough to accept programming of the computer to meet various strategies desired by the car manufacturer using the transmission.”
In past TASC Force™ Tech Tips, I have stressed the benefits of testing electrical circuits by measuring current draw. I have also commented that finding new information adds pieces to the puzzle and helps to bring the whole technical picture into better view. This month’s topic is an example of using current-draw testing to uncover an additional cause for 2-3 shift flare on 4L60-E transmissions.