If your transmission is sending up smoke signals, then there could be a problem with your modulator. Replace old factory preset models with TCI adjustable vacuum modulators. These transmission modulators are available for several applications and allow you to fine-tune your shift points and shift feel. Simply adjust the screw inside of the vacuum nipple for more or less diaphragm preload. Your transmission relies on the vacuum modulator to function properly, and you can rely on TCI and their adjustable vacuum modulators for renewed performance and the ability to slightly raise or lower part throttle shift points and line pressures.