Originally Posted by SSpdDmon
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The next two graphs help you to see where the TCC will apply and release in relation to the shifts that can affect it. The first one (TCC 3rd Gear) is a little tricky because sometimes people cruise around in D instead of (D). Here you want your TCC apply to be greater than or equal to your upshift AND greater than your TCC release. Technically the PCM will command the TCC to release for a downshift, but I like to keep the TCC release slightly higher than the downshift. That way, if a downshift is commanded, the TCC is already disengaged. It also serves to let the converter 'work' in certain scenarios. For example, say the car is slowing down going up a hill even though you're giving it 25% throttle. The TCC will release and you can make use of the toqure multiplication of the stall before it'll downshift into the lower gear. So, the general rule for this graph is:
(3-to-2)<(3rd Rel.)<(3rd App.) AND (3-to-4)<(3rd App.)
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