I have an old Chevy pickup with 454 engine and 3 speed THM400.
I just put a new tranny modulator in it as old one leaked and allowed tranny fluid to get past diaphragm.
New one is Fram FM2321, with green stripe, same as my old one. It is adjustable, as was the old one. Does anyone know which way to turn the screw, and what to look for?
Regards,
Henry
Turning the screw clockwise will raise the part throttle shift points.
THANK YOU for the info. I couldn't find it anywhere on the 'net.
Henry
John Kunkel wrote:
It turns clockwise to raise the shift points - counterclockwise to lower the shift point. I usually try to set it where the 1-2 shift occurs at 8-10 mph at minimum acceleration on level ground. The modulator controls the
1-2 shift. If you set it too high, you will get a delayed or hang shift under load. This is a seat of the pants adjustment to some extent. You will know when you get it right. You should adjust it in about 1/8 turns at a time once you get it in the ballpark.Lugnut
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