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Conversions FAQ Index

General questions pertaining to Five/Six speed conversions. Be sure to contact us if you do not see an answer to your question.

  • Can a T-56 be installed behind a four speed bellhousing?

    yes it can with an adapter plate. Call us for your application.


  • My car is equipped with a 4 speed, can it be removed and a TKO installed in it's place? I heard the bolt pattern was the same.

    Yes a Tremec 3550/TKO/TKO500/TKO600 have the same transmission bolt pattern as a toploader but with a longer input shaft. The input shaft can be shortened or a spacer plate can be added to make up the difference. Which way to go depends on the car. Cobra's benefit from the shortened shaft for easier installation/removal. Mustangs with consoles benefit from the spacer plate to center the shift lever in the opening.


  • What are my options for installing a five speed into an early model Mustang?

    There are many different ways a five speed can be installed. There are several types of bellhousings and adapter plates to make it easy. Which bellhousing or adapter depends on which motor you have, or what type of clutch linkage is desired. Start with this article in Tech Alley for details and options available.


  • Does the driveshaft have to be shortened with installing a T-5?

    In most cases it does. The input shaft is 3/4" longer. Whether you use a T-5 bellhousing or an adapter plate, the transmission comes back 3/4" of an inch. This means the drive shaft has to be shortened the same and rebalanced. Some cars, the drive shaft is already too short and may not need to be shortened. A properly fitting driveshaft should have about 3/4" of slip yoke showing behins the tailshaft seal. Ready to bolt in driveshafts are available in both steel and aluminum.


  • Does a stock appearance shift lever bolt on all aftermarket shifters?

    Not all aftermarket shifters use the stock T-5 bolt pattern that the shift lever used. Shifters like the stock appearance shift lever use the stock T-5 bolt pattern.


  • Is a five speed conversion reversible?

    Yes very much so, in general. However, if you are installing a Tremec TKO or T-56 into certain vehicles where the trans tunnel needs to be modified to get it to fit, then the reversal process is more involved.


  • Can a conversion be installed and retain a stock appearance?

    Yes, very much so. The level of how stock you wish the car to appear is up to you. We have kits that use the stock linkage and OEM appearance shift lever, ball and boot.


  • Will stock crossmember work for a T-5 or TKO?

    No, the mounting points are much different and does require a crossmember made for each transmission. See our online catalog for crossmembers that are available. 1965-66 Mustangs that are converted using a TKO can use the stock crossmember when the floor support is moved further back to help make room for the larger TKO case. This is the reason we do not offer a 65-66 Mustang TKO crossmember. Call us for the rest of the details for this application.