How to Replace Shocks & Struts on a GMC Sierra

In this article you will learn how to install a loaded straight assembly on a GMC Sierra . 

With a loaded strut assembly, you don’t have to don't have to take the assembly apart to get to the strut. Instead of taking an old assembly out, then removing just the spring from the strut, you get to put in this whole new assembly, which includes a new strut mount, insulator, dust boot, new coil spring and the strut itself. With the Loaded Strut Assembly, that's all in one piece.

What Tools will I need to Replace the Loaded Strut Assembly on a GMC Sierra?

You can do this job at home with hand tools. You will need the following:

  • Torque wrench. 
  • Mallet
  • Half inch breaker bar
  • ⅜ Extra Long extension
  • 22 millimeters socket
  • 21 millimeter socket
  • 18 millimeter deep well socket
  • 15 mm deep well socket
  • 3/8″ ratchet 
  • ½” ratchet
  • 15 millimeter wrench
  • 21 millimeter wrench.
  • Safety gloves
  • Safety Glasses

You might want to use some PB blaster to loosen up some of those joints.

Steps to Install a Front Loaded Strut Assembly

AutoZone How to Replace Shocks Struts on a GMC Sierra step 1

1. Loosen and remove top strut mount nuts

Find the three top strut mount nuts under the hood. Use a 15 millimeter deep socket with a 3/8 inch extra long extension to loosen and remove them. It’s easier to access these nuts while the truck is on the ground.

AutoZone How to Replace Shocks Struts on a GMC Sierra step 2

2. Raise the vehicle and remove the wheel

Once you’ve got the nuts loosened to be removed, we’ll need to get the truck raised and the wheel off to access the strut inside the wheel well, break the lug nuts on the wheel with a socket breaker bar. Then jack up the car. A jack standard secure part of the frame and lower the car onto it.

AutoZone How to Replace Shocks Struts on a GMC Sierra step 3

3. Remove lug nuts

Take off the lug nuts and remove the wheel. Now you can access the strut assembly.

AutoZone How to Replace Shocks Struts on a GMC Sierra step 4

4. Remove the old strut assembly and slide in the new

You’re gonna want to locate the two bottom bolts on the strut assembly, loosen and remove them with a 15 millimeter deep socket. You won’t need a wrench here because the nuts are fixed onto the structure.

Once the bolts are out, just slide out the old assembly.

Since we have a Duralast Loaded Strut Assembly, we can just go ahead and install the new assembly.

AutoZone How to Replace Shocks Struts on a GMC Sierra step 6

5. Tighten the top nuts and bottom bolts of the new assembly

Now you should be able to access the top studs through the wheel well. With your fingers. tighten the top nuts supplied with the new strut to hold the assembly in place. We’ll tighten them all the way through the hood later.

Reinstall the bottom bolts and tighten. The torch spec this torques to 37 ft. lbs.

If you can reach the top nuts while the truck is raised, go ahead and tighten them under the hood with the ratchet and extension. If not, get them as tight as you can and then tighten all the way after the wheel is reinstalled and the car is lowered

AutoZone How to Replace Shocks Struts on a GMC Sierra step 7

6. Reinstall the wheel and lug nuts

Reinstall the wheel and lug nuts. Lower the car until the wheel is touching, then tighten the lug nuts all the way. These lug nuts should be tightened to 140 ft. lbs. of torque.

Repeat on the other side and you’re ready to move to the rear.

How to Replace Rear Shocks on a GMC Sierra

1. Jack up your vehicle

For the rear, install jack up the car, place it on jack stands and remove the wheel. Following the same process we use for the front. You may want to place the jack under the rear differential of the vehicle.

2. Remove the old shock and install the new

Use a 21 millimeter socket and 21 millimeter wrench to loosen and remove the bottom nut on the shock.

Now remove the bottom bolt. You may need a mallet and a punch to get it all the way out.

Remove the top nut with a 21 millimeter socket.

And now we just take the shock out and then we just install the new shock.

3. Line up the new shock

Get one of the top bolts started to line up the shock. Then compress the shock and slide it into the bottom, insert the bottom pole, install the nut and tighten.

Now you can tighten the top nuts. These are also torqued to 85 ft. lbs.

4. Put the wheel back on

Now put the wheel back on using the same steps outlined for the front and lower the car.

Repeat on the other side and you’re done.

Remember you may want to take your car in for an alignment after any suspension job, and take the car for a test drive to enjoy your new ride. You can check out our network of auto repair shops in your area.

Advice, how-to guides, and car care information featured on and AutoZone Advice & How-To’s are presented as helpful resources for general maintenance and automotive repairs from a general perspective only and should be used at your own risk. Information is accurate and true to the best of AutoZone’s knowledge, however, there may be omissions, errors or mistakes.

Be sure to consult your owner’s manual, a repair guide, an AutoZoner at a store near you, or a licensed, professional mechanic for vehicle-specific repair information. Refer to the service manual for specific diagnostic, repair and tool information for your particular vehicle. Always chock your wheels prior to lifting a vehicle. Always disconnect the negative battery cable before servicing an electrical application on the vehicle to protect its electrical circuits in the event that a wire is accidentally pierced or grounded. Use caution when working with automotive batteries. Sulfuric acid is caustic and can burn clothing and skin or cause blindness. Always wear gloves and safety glasses and other personal protection equipment, and work in a well-ventilated area. Should electrolyte get on your body or clothing, neutralize it immediately with a solution of baking soda and water. Do not wear ties or loose clothing when working on your vehicle.

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