TF-60SN Accumulator Body Caution
Questions? Email Sonnax Tech Support about this article.
So you've got it figured out. The cause of that TF-60SN converter issue you've been fighting has finally been narrowed down to wear in the lockup clutch control bore. Well, before you reach for that pot of gold at the end of the rainbow, here are a couple of things you should know.
There are actually two different versions of the TF60-SN accumulator body in circulation. Figure 1 shows the visual difference between the two castings.
This is the simplest way to identify which style you have. Figure 2 shows that although it is not as obvious, there is a difference between the parts used in the two versions. Look closely at the spring end of the valve.
The good news is the same valve repair kit for the lockup clutch control bore can be used to repair either version. The catch is: the installation procedure is not the same, due to the bore length difference.
Why is the install procedure so critical? If the late body install procedure is used in an early body, the mistake will be frustrating but obvious; it will not all fit in the bore. At least you will know you have a problem. However, if an early body install procedure is used in a late body, you will be able to install the parts, re-assemble the unit and reinstall it into the vehicle. You may not discover that you do not have lockup until the road test.
Figures 3 and 4 show the line up difference between the two installation procedures. Early style accumulator bodies, having the shorter valve body bore length, use the valve/sleeve, spring, and plunger/sleeve combination. Later style bodies, due to their longer bore length, use all the same components plus a valve stem cap and a spacer, to make up the length difference.
Remember that TF-60SN is the AW designation. You may see and recognize this unit under a variety of names. VW 09G, 09K and 09M are common to many of you, with 09G often used to refer to any of the three. BMW/Mini builders know this unit as the 6F21WA. Regardless of the label or designation, the other thing you should remember about this unit is that the accumulator body is extremely small and not easily secured for reaming. You should purchase or fabricate an adapter plate that will allow you to securely mount and accurately position this valvebody section for reaming. (Figure 5).
Once you have identified and used the appropriate installation procedure, you will be on your way to that pot of gold and a happy customer.
Sonnax would like to thank Valve Body Xpress for bringing this issue to our attention and working with us to solve this problem.
Tory Royce is a Sonnax Technical Support Specialist and a member of the Sonnax TASC Force® (Technical Automotive Specialties Committee), a group of recognized industry technical specialists, transmission rebuilders and Sonnax Industries Inc. technicians.
While Sonnax makes every effort to ensure the accuracy of technical articles at time of publication, we assume no liability for inaccuracies or for information which may become outdated or obsolete over time.