If you’ve inspected your rear sway bar / anti-roll bar bushings in your DB9 and discovered they need changing (see my other article on this – coming soon), this article is for you. The good new is that the process is pretty simple once you have access to them, but take note below of the special tightening procedure. Read on to learn how.
This is one of the few projects that won’t break the bank. The only parts you’ll need is a new pair of bushings. I spent a considerable amount of time looking for a set of aftermarket polyurethane performance bushings (that you can get for most any other mass produced sports car), but struck out for the DB9. If you know of anyone making one, please leave me a comment down below so I can share with everyone.
Fortunately the official Aston Martin parts aren’t that expensive. You’ll need a quantity two (2) of Aston Martin part number 4G43-5484-CA. [Note: This part number is ridiculously close to the one for the Front bushings, but they are in fact different parts] You can find these online for about $20.67 USD each. Or you can contact Richard Hayward at HWM England and get them a little cheaper for about $18 USD. Email Richard the info about your car (and tell him you heard about him from Aston1936.com) and he’ll be sure you are getting the right parts at the right price. [Note: HWM can’t ship to the USA any longer due to a ridiculous Aston Martin imposed ban protecting the US dealerships, but they can ship to the rest of the world]
You don’t need much in the way of tools:
- 10mm socket
- Ratchet and extension
- Speed driver (optional)
- Torque wrench suitable for 30 Nm (22 ft-lbs)
- An inspection light can always be handy
Before you can start on the bushings, you have to do a bunch of work to get to them. They are covered by the front aerodynamic undertray, so you’ll have to remove that first. You can leave the wheels on. I tackled swapping my bushings while I already had the car up on stands for my annual service, so you might consider that as well. Here are some other articles to help you get to that point:
I checked the Official Aston Martin Workshop Manual Section 4.02 on the rear suspension to learn how Aston wants it done. It’s not really covered separately, but can be summarized as “Install both bush straps and torque the fixings”. It’s worth noting that the torque for the rear bolts is higher than those in the front of the car (30Nm vs. 24Nm), a fact I missed when I shot and created the video, and only spotted again now re-reading the manual.
Once you have access to them, the process of changing the bushings will only take about 10 minutes.
- Starting on one side, remove the two bolts holding the sway bar bushing retaining strap in place using your 10mm socket, extension and ratchet.
- If both wheels are hanging evenly the sway bar is not under load, so you should be able to work without worrying about something springing out in your face!
- Pull the retaining strap off the bushing. You might need to pry it off gently with a screwdriver as it may be holding the bushing tightly.
- Note the position of the two rubber tabs on the old bushing There should be two tabs, facing rearward above the center.
- Pull the old bushing off the sway bar. It’s split in the back, so you should be able to easily pull it off.
- Wipe down the sway bar to remove any dirt or debris
- Fit the new bushing into place, taking note to arrange the tab in the correct position.
- Slide the bushing along the sway bar until its up against the shoulder of the rib on the sway bar.
- Replace the retaining strap, pushing it firmly over the new bushing.
- Loosely start each of the two bolts, then snug them up evenly using the speed driver or ratchet.
- Alternate top bolt, bottom bolt, back and forth a small portion each time to evenly suck the strap down over the bushing.
- Once snug, follow this specific process:
- Torque one of the two bolts to 30 Nm (22 ft-lbs).
- Torque the other bolt to 30 Nm.
- Go back and re-torque the first bolt again to 30 Nm
- Finally re-torque the second bolt again to 30 Nm
- I think the issue was that when you torque them the first time the rubber of the bushing resists some and the torque on the first bolt doesn’t remain after the second is tightened.
- That’s the first bushing done, now go ahead and follow the same procedure for the other side.
Once the bushings are swapped, all that’s left is to put the undertray back on and get the car off jack stands. These articles might help with that:
If you are going to tackle the front sway bar bushings too, please check out my other article and video on this showing you how.
Here is a short video showing you how to inspect and change the bushings following the process described above.