Here's a general overview of the steps involved. Remember, these are *general* steps and may vary slightly depending on your specific engine and transmission:
1. Preparation is Key:
* Safety First: Disconnect the negative battery terminal. Use jack stands to securely support the vehicle. Wear safety glasses and gloves.
* Gather Tools: You'll need a variety of tools, including wrenches (metric and possibly standard), sockets, ratchets, a transmission jack, possibly an engine hoist (depending on your approach), pry bars, a torque wrench, and plenty of rags.
* Drain Fluids: Drain the transmission fluid completely. This will save a messy cleanup later. Also drain the engine coolant if necessary, as some components may need to be removed.
2. Disconnect Components:
* Driveshaft: Disconnect the driveshaft(s) at the differential and transmission.
* Clutch Cable/Hydraulic Line: Disconnect the clutch cable or hydraulic line from the transmission.
* Shift Linkage: Disconnect the shift linkage from the transmission.
* Speedometer Cable: Disconnect the speedometer cable (if applicable).
* Electrical Connectors: Disconnect any electrical connectors attached to the transmission.
* Exhaust System (Possibly): You may need to loosen or remove parts of the exhaust system for better access.
3. Remove Supporting Components:
* Crossmember: Depending on your approach, you may need to remove or partially loosen the transmission crossmember to gain enough clearance. This often requires removing bolts and potentially lowering the crossmember.
* Starter: The starter motor may need to be removed to provide better access.
4. Remove the Transmission:
* Transmission Jack: Use a transmission jack to support the transmission's weight. This is crucial to prevent damage and injury.
* Transmission Bolts: Carefully remove the bolts securing the transmission to the engine. These bolts are usually located at the bellhousing.
* Lower the Transmission: Slowly lower the transmission using the transmission jack. Be mindful of the clutch fork and any other components that might get caught.
* Guide the Transmission: Carefully guide the transmission out from the engine bay.
5. Clean Up:
* Once removed, thoroughly clean the transmission mating surfaces on the engine and transmission.
Important Considerations:
* Clutch: Replacing the clutch is highly recommended while the transmission is out. This is a good time to inspect the flywheel and pressure plate as well.
* Pilot Bearing: The pilot bearing, which sits on the crankshaft, should be inspected and replaced if necessary.
* Input Shaft Seal: Replace the input shaft seal while the transmission is out.
* Professional Help: If you're not comfortable with this level of mechanical work, consider taking your Jeep to a qualified mechanic. Improperly removing or installing a transmission can cause significant damage.
This is a simplified overview. Refer to a repair manual for detailed, step-by-step instructions specific to your 1988 Jeep Comanche. Remember safety is paramount. If you're unsure about any step, seek professional help.
