Here's a general outline of the process. Remember, this is a simplified overview and may not be completely accurate for your specific vehicle:
1. Preparation:
* Safety First: Disconnect the negative battery terminal. Support the vehicle securely on jack stands. Wear safety glasses and gloves.
* Gather Tools: You'll need a transmission jack (highly recommended), various sockets and wrenches (including possibly a deep socket for the transmission drain plug), a pry bar or seal puller, a new seal, rags, transmission fluid, and possibly a torque wrench.
* Drain the Transmission Fluid: Completely drain the transmission fluid into a suitable container. This is crucial to minimize mess and damage.
* Disconnect Components: Depending on the specific model and transmission, you may need to disconnect the driveshaft, possibly the cooling lines, and potentially other components to access the seal. Your repair manual will guide you on this.
2. Accessing the Seal:
* Remove the Transmission Bellhousing: This is usually the most significant step and often requires removing the starter, some bolts on the bellhousing, and potentially the flywheel or flexplate (if applicable). This is where a transmission jack is invaluable to safely support the transmission as you loosen and remove these components.
* Locate the Seal: Once the bellhousing is removed, the front transmission seal should be visible. It's typically located where the transmission output shaft meets the transmission case.
3. Removing the Seal:
* Use a Seal Puller (Recommended): This is the cleanest and safest method. A seal puller is specifically designed to remove seals without damaging the transmission case.
* Pry Bar (Less Recommended): A small, flat pry bar can be used carefully to pry the seal out. However, there's a high risk of damaging the transmission case if you're not extremely careful. Work slowly and evenly around the seal's perimeter.
4. Installation of the New Seal:
* Clean the Housing: Thoroughly clean the transmission case where the seal sits to ensure a good seal.
* Install the New Seal: Gently tap the new seal into place using a socket that matches the seal's outer diameter. Use a mallet and work evenly to avoid damaging the seal. Do not force it.
5. Reassembly:
* Reverse the Removal Process: Carefully reinstall all components removed earlier, including the bellhousing and driveshaft. Pay close attention to torque specifications.
* Refill with Transmission Fluid: Fill the transmission with the correct type and amount of transmission fluid, following your repair manual.
* Check for Leaks: Inspect for any leaks after reassembly.
Important Notes:
* Transmission Jack: Using a transmission jack is strongly recommended to prevent damage to the transmission.
* Repair Manual: A service manual specific to your 1992 Chevy Blazer is essential. It provides detailed diagrams, torque specifications, and step-by-step instructions.
* Professional Help: If you're not comfortable with this repair, consider taking your Blazer to a qualified mechanic. Improper repair can lead to significant damage.
This is a complex repair. Consult your repair manual and if unsure, seek professional assistance. Improperly performing this repair could severely damage your transmission.
