- Do It Yourself Auto Repair
Chevy Avalanche Shock Absorber Installation Tips to Get That New Truck Ride Back
The rear shocks on most pickups resemble these from a Jeep Liberty
The shock absorbers on your Chevy Avalanche help to isolate the bed and body from the road as you drive. They do this by damping the oscillations that driving on uneven roads induce. If you’ve seen cars driving down the road bouncing like a person on a bungee cord, you’ve seen prime examples of motorists that need new shocks. Shock absorbers that aren’t doing their job are dangerous because they degrade the amount of control you have of your vehicle. They also cause tire wear issues, causing a tread wear pattern known as cupping.
Typical rear suspension on an older vehicle
How Can You Tell If Your Shocks Need Replacement? Check Them!
There’s three ways you can tell if you need to install new shocks on your Chevy Avalanche. If the shocks are wet and oily wear the piston enters the shock body, they’re leaking and need to be replaced. Run your palm across your tires. If you feel hills and valleys, that’s cupping and indicates shocks that need replacement. The last test is called the ‘jounce test.’ Place your knee on the bumper at one corner or the truck and firmly and quickly push down on the bumper and release it. Now count the number of times the body bounces. One or two times is ideal. Three times and you should consider a new shock absorber installation. Anything more than three times and they really need to be replaced.
Replacing the Front Shocks On Your Avalanche
You’re going to need a socket set for this job. If your truck sits too low to the ground to get under it comfortably and safely, you’ll also need at least one jack stand and a jack. Some repair manuals say you have to remove the front wheel to get the shock out. If you can reach the nut on the top of the shock at the top of the coil tower without removing the wheel, you won’t need to remove the tire. Otherwise, you’ll need to lift the front end and remove the tire. Using the ratchet and a socket of the proper size (usually 9/16 inch) turn the nut counterclockwise and remove it. Refer to the picture to get an idea of what this area looks like. Next, from under the center of the lower control arm, remove the two bolts securing the bottom of the shock absorber to the control arm. These bolts are usually either 9/16 or 5/8 inch. Again, refer to the supplied image to see what you’re looking at. Installation is completed in the reverse order of removal. Torque these nuts and bolts to 37 foot-pounds.
The rear suspension on your truck (Ford, Chevy, Dodge, etc) will resemble this Hummer
Rear Shock Absorber Replacement
Replacing the rear shocks is even easier than the fronts. You may need to place your jack under the differential housing or frame to adjust vehicle height to help you get the bolt holes to line up with the rear shock mounts. Pick a side and slide under the truck with the new shock absorber, your ratchet, sockets and wrenches. The nuts and bolts on rear shocks are usually 5/8, 11/16, or ¾ inch. Remove the lower mounting bolt and nut by turning them counterclockwise with the wrench on the bolt and socket and ratchet on the nut. Next remove the upper mounting bolt by turning it counterclockwise with the ratchet and socket on the nut and the wrench on the bolt head. Lift the bottom of the shock absorber out of the mounting pocket on the axle housing and set it aside. Place the bottom of the new shock absorber into the mounting pocket on the axle housing and insert the bolt the reverse of how it came out. Thread the nut onto the bolt, but leave it loose. Hold the top of the shock absorber in place. If the mounting holes line up, push the bolt through and thread the nut on. Tighten both sets of nuts and bolts, however, if the bolt holes don’t line up, you will need to use the jack to make them line up. If the shock absorber is below the mounting hole on the frame, raise the axle with the jack. If the upper mounting hole on the shock is above the frame mounting hole, place the jack under the frame in front of the rear wheel and slowly lift it until they line up. Install the mounting bolt, thread the nut on and tighten the nut. Both upper and lower mounting nuts should be torqued to 85 foot-pounds.
This is what the rear shocks on your older car look like
Extra Notes and Helpful Hints
Some models and years of the Chevy Avalanche came equipped with an electronic ride control. You will need to refer to your owner’s manual to see if your truck is one of these. If so, follow the directions in the manual to deactivate it. You will also need special shock absorbers. If not, two of the most popular brands of shocks for trucks that are used mostly on the road are Monroe (for “Stock” ride quality) and Bilstein (for a more performance type ride) The Monroe part numbers are 39104 for the front and 911506 for the rear. The procedures outlined above aren’t specific to just the Chevy Avalanche, but almost any truck on the road today, as well as most older cars.