Transmission is the key weak point of the car. Lots of people have various problems with it ranging from minor to significant. But it really mostly come from
- Bad software in the early models that was corrected later
- Lack of fluid service schedule
Do these 2 things and the following additional low cost services will keep it running nice for a long long time. Of course, you have to start doing this early in the transmission’s life, otherwise, too much damage may have been done.
Furthermore, diagnosing the exact problem seems quite difficult. Often, it is a little bit trial and error to go through all the typical problem areas. I get the sense from reading the forums most dealer service departments typically goes for the repair that guarantees the fix (replacing the transmission). But it is also the most expensive (~$4000 or more). I’d imagine if dealers do these smaller repairs first but doesn’t fix the problem. They probably get unhappy customers.
So here are a check list for low cost remedies
- If you have year 2001 or 2002, check your transmission serial number to see if you have a defectively design B4 servo cover. See here.
- Change your transmission fluid. See here and here.
- Check your lower transmission torque mount. See here.
- Make sure you have the latest transmission software installed. See here. Might do the adaptation too (it will cost more). The adaptation (see here for more details) is basically a particular driving pattern that trains the transmission computer to shift as smooth as possible based on the current conditions in the transmission. It is possible to have dealer tech just turn on the adaptation mode and you go ahead and do the driving patterns yourself. If you can convince your dealer to do this, before to get the driving pattern directions. I’d do the adaptation after all above items are checked and/or corrected first.
- Try some Seafoam Transtune to see if it improves. ipd guys seems to have tried it with good results. ipd TransTune product link
- The transmission computer software can adapt its shifting parameters. It basically adapts the actuation of internal solenoids based your driving style and transmission’s internal condition. To do the adaption, see here.
- Install an external ATF cooler. Most transmission problems show up when the ATF is hot. A few people have noted surprisingly positive results with an external cooler. See here