First off, MAKE SURE YOU HAVE SOMEONE WHO KNOWS HOW TO DIAGNOSE THIS TRANSMISSION PROPERLY BEFORE ATTEMPTING TO DO ANY REPAIRS OR REPLACEMENT. It has been my finding that most transmission shops as well as general auto mechanic facilities do not know how to diagnose and repair this specific VW transmission. Many VW automatic transmission owners will eventually run into one or more of the following dreaded O1M problems. The most common of these problems are:
1. Hard 2-3 shifting
2. Hard 3-4 shifting
3. Flared shifts (as you accelerate the RPMs rise but the car does not go any faster)
4. False neutral (when you come to a stop and try to accelerate the motor revs and eventually jumps into gear causing the car to lurch forward)
5. Occasional fluctuation of RPMs while driving at a consistent speed
6. From a dead stop the vehicle seems to start in third gear when accelerated
7. Hard shifting
8. Poor fuel mileage
The first major problem is that VW claims the transmission fluid is “lifetime fluid”. The usable life of a vehicle, which is rated by the EPA, is between 100,000-120,000 miles. What I find interesting is that most car manufactures only warranty their vehicles for a maximum of 100,000. This means that any repairs after 100,000 miles will be solely on the owner of the vehicle. With that said, I like to change my 01M transmission fluid at every 60,000 miles.
The second major problem is the valve body. The valve body is made of aluminum, which is a nonferrous metal. Because of this the valve body wears out. I believe that a big reason the 01M gets a bad name is because the valve body wears, which in turn causes the transmission not to have proper pressure to the clutch packs. By not having proper pressure this causes the clutch packs to wear prematurely. Continual driving just makes matters worse and the transmission eventually needs a full rebuild. If caught in time, the valve body can be replaced, and the transmission can possible gain many more years of operation. Having a proper diagnosis and road test is crucial.
The third problem for longevity, is the transmission cooler. I have noticed on hot days transmission temps can get up to 240 degrees or more for sustain periods of time. Heat is never a good thing! There are after market transmission cooler kits that I have seen drop the transmission temperatures almost 100 degrees Celsius. Remember that the 01M transmission is a temperature dependent transmission. Even to check the transmission fluid level the fluid needs to be around 85 degrees Celsius. Higher temperatures lead to early fluid breakdown, slippage and torque convertor surging.
Another common problem is the transmission wiring harness. The factory harness is a ribbon harness and sometimes can break internally in the harness causing the transmission not to shift. I like to replace the ribbon harness with the new updated round wire harness. I have not run into any problems with them yet.
But wait is there hope for me??? YES!
The first thing to do is have your car scanned with Vag-com in order check the behavior of what the transmission is doing. Second is to evaluate the age of the transmission, current mileage, and how many times the transmission has been serviced. If the transmission is a candidate for the valve body replacement I suggest you go with the Sonnex moded valve body.
All statements made are solely my opinions and the final decision is solely the responsibility of the vehicle owner. My opinions are given in order to educate people from my personal experiences.
Volkswagen transmission problems (the dreaded O1M):