Recently my wife and I purchased a 120k mile XC90. With the advent of our second daughter and we being on the taller side our low-slung SAAB 9-5 Aero wagon was getting hard on our (her) back. With any used car purchase there are normal wear and tear items that need attention, and suspension is one of those things to keep an eye on at this mileage. Here’s my XC90 Rear Shock DIY.
Following her home the other day I noticed the back of the car was quite bouncy, especially going over some low-speed speed bumps. The ride inside the car was pretty good, but it was feeling a little tired and I was fairly certain that the OEM Sachs struts were original to the car. A quick check by VIN verified that this car did not have self-leveling NIVOMAT suspension installed. Because of that, I had multiple options to choose from, a Genuine Volvo, Sachs, or Bilstein. I do enjoy a good Bilstein shock, but this being primarily a people mover without doing any towing or heavy hauling, I went with the Volvo designed OE part. Since Sachs makes the shock for Volvo with a quite a savings in cost, the choice was clear.
So on to the install. On paper it looks quite easy, just one nut and one bolt, but in reality there are a few tricks and tips I can offer after completing the job successfully.
First, the lower shock mount bolt is very obvious and bolted to the lower control arm. It can be zipped off with your favorite impact gun or hand tool. You may need to apply some pressure with a floor jack to remove the tension from the spring and slide the bolt out.
The upper mount nut is a little more hidden. If this is the first time these have ever been done in your car you will have to cut through several layers of sound deadening under your 3rd row seats (or trunk if you don’t have them. Don’t worry, it sounds scary , but is very easy and Volvo has made it fairly easy to do. Pushing your seat bottom to the stowed position you’ll see a faint depression in the carpet . This is there to guide where you have to cut back the carpet to access the upper shock nut.
Take out your razor and start tracing the line, cutting deeper until you are all the way through the foam. Be aware that it is quite thick., over an inch in some places! Once you’ve made your cut you can pull the carpet back and you’ll see an oval cover that can just be peeled off. Below that reveals yet another cover that needs to be twisted off to finally access the nut.
The business of actually removing the nut is also not as simple as it looks. Depending on the age and environment the car is driven in, it can be quite rusted. A liberal application of penetrating oil and a wire brush is recommended to remove as much corrosion off the old nut and threads as much as possible. The worst thing you can do is strip out the Torx socket that keeps the shaft from moving. After you’ve cleaned this as best you can, you might get lucky and zip it off with an impact gun, but if not you’ll have to employ Volvo special tool that we offer for customers looking to do the job right. https://www.eeuroparts.com/Parts/58170/Shock-Removal-Tool-9995500/ This will allow you to turn the nut while you keep the stud steady. In a pinch you can also use an 18mm open ended wrench and T40 Torx on an extension. One to keep the nut steady as you turn the Torx in the opposite direction (clockwise to loosen). If it tightens up just run the nut back the other way, spray it down some more and clean the threads until it comes free.
Once free, a small tap or pry from a bar will drop the shock down through the spring. At this point the shock mount should come down with that. You’ll probably want to replace this.
Next you’ll line up the new mount and shock back up through the spring and seat it in the control arm, it should stay there without the bolt holding it in so you can check top-side that you have everything lined up correctly. If everything is good, zip the nut on and the lower bolt on and move on to the other side. Again, the nut will cause the shaft to spin if doing by hand, so you’ll need to hold the nut steady.
Once you’ve completed both sides, you replace your covers and tuck your carpeting back together and enjoy your new cushy ride.