Hi I have a 2000 Bonny SSEi that has developed a hard shift when changing gears in the lower gears at very low revs and when it is up to normal operating temperature. It doesn't do this when the power is on, i.e hard accelerating. This is beginning to be quite the bump when changing, I was wondering if it could be a modulator valve or something in the throttle body has gone awry. Thanks for any help. Les.
Older transmissions had a vacuum modulator, and engines have a throttle body. Modern transmission still have a valve body.
Your trans is entirely electronically controlled. Not all scan tools have full transmission control computer functionality, so you may need to go to a GM dealer if you are not in an area where the trans shops are up do date on modern technology. GW
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