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TCI Automatic Transmission Dos & Don'ts

Use this page as a guide for the Do's and Dont's on your TCI Automatic Transmission. Please call TCI® at 800 999 0853 or E-mail us if you have any questions about your new TCI® transmission.


  • Back flush cooler to prevent contamination of new transmission and converter.

  • If you intend to install a used converter, have it professionally flushed and fully inspected before using it. Proper inspection includes measuring pilot, hub, endplay and overall length and comparing those to the manufacturers' specifications.

  • Verify that converter is property installed in transmission before bolting unit into vehicle. Refer to enclosed instructions.

  • Thoroughly inspect your flexplate and drive shaft before installing transmission. Look for bad teeth, cracks, loose or missing balance weights, worn yoke or universal joints. These problems will cause vibration and other damage.

  • ALWAYS install and adjust any required TV or kickdown cables exactly according to the instructions. Inadequate pressure will quickly destroy your transmission. Refer to enclosed instructions and/or vehicle service manual.

  • Verify shifter adjustment before starting engine. Vehicle should start in PARK and NEUTRAL only.  Also, severe transmission damage will occur if unit is operated between gears. Refer to shifter instructions or vehicle service for procedures.

  • Check that the transmission cooler lines are not kinked or touching the exhaust system.

  • If your transmission is equipped with a vacuum modulator it is very important to verify amount of vacuum at the modulator with a gauge. Automatic transmissions typically need a minimum of 12 in. Hg. at idle. Throttle position increases should produce a quick decrease in the vacuum reading at the modulator. Not enough vacuum will cause late, harsh shifts. Slow response to throttle position changes due to a kinked or plugged line will not property boost line pressure and will burn up your transmission.

  • Add at LEAST 4 quarts of transmission fluid to transmission before starting engine to prevent damage. Continue filling with engine running to proper level.

  • Re-torque the oil pan bolts after installation to 13 ft.-lbs. to prevent leakage.

  • Run your transmission with the vehicle on jack stands, or a floor jack with a transmission jack adapter, so that any mis-adjustments are corrected before they can cause damage.

  • Replace the TCI® installed filter after initial use. (Race - 20 passes; Street - 500 miles) Bushings and clutches in an automatic have a break-in that generates fiber and metallic particles.


  • Don’t accept your transmission from the delivery driver until you personally inspect it for cracks, dents or breakage.

  • Never install a converter of unknown specifications or origin. It could be the wrong application or, if damaged, it could ruin your new transmission.

  • Don’t attempt to use a kinked metal or all rubber hose to connect your vacuum modulator if applicable. Proper installation is a metal line carefully bent, with just a few inches of rubber hose on either end for connection.

  • NEVER install a TV cable on a Holley carburetor without the proper brackets. Your transmission will burn up as a result of inadequate operating pressure. TCI®carries a bracket designed specifically for Holley carbs.

  • Never use a solid transmission mount in any circumstance. This WILL cause the case to crack because it is not designed to be a stressed member of the chassis.

  • Never install pipe plugs in the cooler fittings. A cooler loop, in the very least, should be installed so that transmission lubrication is not compromised.

  • Don’t use Teflon tape when installing cooler fittings into the case or the case WILL crack.

  • Don’t overfill your transmission because this will foam and aerate the fluid causing heat and low pressure problems. Be sure the dipstick and tube are correct for your application.

  • Don’t use the vehicle if a problem is suspected with your new transmission. Many times problems can be rectified while the transmission is still in the vehicle, but, if the transmission suffers permanent damage it will need to be removed.