Here's a general outline of the steps. Consult a factory service manual specific to your 1971 Chevelle for detailed instructions, torque specifications, and diagrams. Variations exist depending on the axle type (e.g., 10-bolt, 12-bolt).
1. Preparation and Safety:
* Safety First: Disconnect the battery's negative terminal. Use jack stands to securely support the vehicle after raising it. Wear safety glasses and gloves.
* Gather Tools: You'll need a variety of tools, including jack stands, a floor jack, socket wrenches (various sizes), a breaker bar, a torque wrench, penetrating oil, a transmission jack (highly recommended), possibly a wheel puller, and possibly a spring compressor (depending on the type of leaf springs).
* Drain the Differential: Drain the differential fluid to minimize mess.
2. Disconnect Components:
* Drive Shaft: Disconnect the driveshaft from the differential. This typically involves removing bolts at the differential yoke.
* Brake Lines: Carefully disconnect the brake lines from the rear axle housing. You'll likely need a flare nut wrench and may want to use line plugs to prevent fluid loss. Be prepared to bleed the brakes afterwards.
* Shocks: Remove the shock absorbers from their mounting points on the axle and chassis.
* Exhaust System: Disconnect any exhaust components connected to the axle housing.
* Leaf Springs (or Coil Springs - less common on a '71 Chevelle): This is the most challenging part. If you have leaf springs, you'll likely need to remove the U-bolts holding the springs to the axle. A spring compressor is highly recommended to safely compress the springs before removing the U-bolts. If you have coil springs, you'll need to separate the springs from the control arms and axle.
3. Remove the Axle Assembly:
* Lower the Axle: With the suspension components disconnected, use a transmission jack (or a very strong floor jack) to carefully lower the differential assembly. Support it evenly to avoid damage.
* Remove the Axle: Once the axle is lowered enough, you should be able to maneuver it out from under the car. It can be heavy, so have help if needed.
4. Reassembly (Reverse Order):
* Reassembly is the reverse of disassembly. Pay close attention to torque specifications for all bolts. Incorrect torque can lead to failure. Properly bleeding the brakes is crucial after reconnecting the brake lines.
Important Considerations:
* Axle Type: The specific procedure will vary depending on whether you have a 10-bolt or 12-bolt rear end. The 12-bolt is generally more robust.
* Service Manual: A factory service manual is invaluable for this job. It will provide detailed diagrams, torque specifications, and step-by-step instructions specific to your vehicle.
* Professional Help: If you're not comfortable with this level of automotive repair, consider seeking professional help from a qualified mechanic. This is a complex job that can easily lead to damage if not done correctly.
This is a simplified overview. The actual process is more intricate and requires specific knowledge and tools. Again, a factory service manual is essential. Attempting this without proper knowledge and tools can result in damage to your vehicle or personal injury.
