1. Preparation:
* Safety First: Disconnect the negative battery terminal. Use jack stands to securely support the vehicle after raising it. Wear safety glasses and gloves.
* Gather Tools and Parts: You'll need a complete set of metric and possibly SAE sockets, wrenches, a transmission jack, a torque wrench, fluid drain pan, and a new transmission (including any necessary parts like a torque converter). Consult a repair manual specific to your vehicle's year and transmission type for a complete list.
* Consult a Repair Manual: A factory service manual or a reputable aftermarket repair manual is absolutely essential. These manuals provide detailed step-by-step instructions, torque specifications, and diagrams specific to your vehicle. This is crucial to avoid damaging your vehicle.
* Fluid Drainage: Drain the transmission fluid.
2. Removal:
* Disconnect Components: Disconnect the driveshaft, shift linkage, cooling lines, electrical connectors, and any other components attached to the transmission. This will vary depending on your specific transmission type.
* Support the Transmission: Use a transmission jack to support the transmission's weight as you disconnect components.
* Remove the Transmission: Carefully remove the transmission from the vehicle. This often involves removing the transmission mount and possibly loosening the engine mounts slightly to provide enough clearance.
3. Installation:
* Inspect and Prepare: Inspect the bell housing and transmission mounting surfaces for any damage. Clean and prepare the surfaces for installation.
* Install the New Transmission: Carefully install the new transmission using the transmission jack. Align it properly with the engine and transmission bell housing.
* Reconnect Components: Reconnect all the components you disconnected during removal, ensuring everything is properly secured and aligned. Pay close attention to the torque specifications in your repair manual.
* Fill with Fluid: Fill the transmission with the correct type and amount of transmission fluid specified in your repair manual.
4. Final Steps:
* Lower the Vehicle: Carefully lower the vehicle.
* Check Fluid Level: Check and adjust the transmission fluid level.
* Test Drive: Test drive the vehicle, paying close attention to the transmission's operation.
Important Considerations:
* Transmission Type: The 1984 Oldsmobile Ninety-Eight Regency likely had either a THM200-4R or a different automatic transmission. The specific procedures will vary significantly depending on your transmission type. Your repair manual will identify this.
* Torque Converter: The torque converter is usually replaced with a new transmission. Be sure to handle it carefully as it is very fragile.
* Professional Assistance: Due to the complexity and potential for damage, strongly consider having a professional mechanic perform this repair. The cost of a professional repair might be less than the cost of damaging components during an amateur attempt.
This is a highly simplified overview. Again, do not attempt this repair without a detailed repair manual and significant mechanical experience. Improper installation can lead to serious damage to your vehicle and potentially injury to yourself. A professional mechanic is the best option for this kind of repair.
