The Borg Warner/Tremec T56 transmission is very well engineered 6 speed that can be upgraded to perform better than the original engineers intended to. Most 6 speed owners want to upgrade to Stage I; Stage II; Level I; Level II, so on and so forth but most people don’t know the reason behind the upgrade.
OEM manufacturers build transmissions with objectives in mind but the bottom line is always the cost. In order to save on costs, they use parts that will be easy to produce and inexpensive to manufacture. For normal street use, these parts stand up quite well and last up to 100,000 miles or more.
When the T56 is out side of street environment, all of that changes. Here are some of the weak parts:
- The 3rd gear is the most commonly missed gear and when pushed hard into 3rd gear, the aluminum 3-4 shift fork can break. (symptom: no 3-4 gears)
- The stamped steel keys in the synchronizers often break into several pieces since it wasn’t built to handle the rigorous shifting. (symptom: stuck in gear and won’t come out)
- The transmission goes through heat cycles every time the vehicle is driven for any length of time but when driven aggressively, the heat can make the plastic shift fork pads brittle. The plastic fork pads often crack and fail. (symptoms: grinding, popping out of gear)
RKT offers a basic upgrade package that replaces all the “weak links” in the T56 with the following parts:
- Billet synchronizer keys
- Steel 3-4 shift fork
- Bronze fork pads
With the above upgrades, the T56 will perform well under all aggressive shifting environments.