1. Prepare the vehicle: Park the vehicle on a level surface, apply the parking brake, and chock the wheels. Disconnect the battery's negative terminal to avoid any electrical hazards.
2. Remove the transmission mount: Locate the transmission mount, usually situated underneath the vehicle and connected to the transmission and the chassis. Remove the bolts/nuts that secure the mount to the chassis and detach it carefully.
3. Disconnect the transmission lines: Identify and disconnect the transmission fluid lines, typically connected to the transmission housing. Be cautious as transmission fluid can leak during this process.
4. Remove the driveshaft: Locate and disconnect the driveshaft from the transmission. This might involve removing the bolts or nuts that hold the driveshaft in place.
5. Unbolt the transmission: Remove the bolts or nuts that secure the transmission to the engine block. It may be necessary to support the transmission with a transmission jack or similar equipment to prevent it from falling.
6. Separate the transmission from the engine: Carefully slide the transmission away from the engine block. This step might require some maneuvering to clear obstructions such as exhaust pipes or electrical wiring.
7. Install the new transmission: Position the new transmission into place, aligning it with the engine block. Reattach the transmission bolts/nuts and secure them properly.
8. Reconnect the transmission lines and driveshaft: Reattach the transmission fluid lines and the driveshaft, ensuring that they are properly connected and secured.
9. Reattach the transmission mount: Reposition and secure the transmission mount to the chassis using the previously removed bolts/nuts.
10. Refill the transmission fluid: Add the appropriate amount of transmission fluid to the transmission through the fill plug. Check the transmission fluid level and add more if necessary.
11. Reconnect the battery: Reconnect the negative terminal of the battery.
12. Test the transmission: Start the vehicle and check for any unusual noises or leaks. Ensure proper shifting and operation of the transmission.
13. Reset the transmission adaptive values (if applicable): Some Mazda 626 models have adaptive transmission systems that learn and adjust shift patterns. Consult your vehicle's manual or a qualified mechanic to perform a reset procedure, if necessary.
Remember, changing a transmission requires a thorough understanding of automotive mechanics and safety procedures. If you are not confident in performing this task, it is advisable to seek professional assistance from a qualified mechanic.
