Subaru Outback Forums banner

New front struts on 99 OB, did I do something wrong?

756 Views 10 Replies 5 Participants Last post by  Yourghostisagift
I’m pulling to the left a little and I’m pretty sure both sides are making a knock noise when I go over potholes/bumps etc. I’ve driven on them for about 250+ miles now but I don’t know much about suspension yet, I heard they could need to be broken in but I have no idea what makes them “knock” I did also make sure to mark the top bolt at 12 o’clock position and tighten it back in the right place.

Automotive tire Locking hubs Motor vehicle Vehicle Vehicle brake

Motor vehicle Automotive tire Hood Automotive design Automotive lighting

Automotive tire Locking hubs Motor vehicle Tread Vehicle brake
See less See more
1 - 6 of 11 Posts
Did you replace the strut mounts? I had a knock on one side of my mazda3 about 5k miles after replacing my struts. Turns out I had a bad strut mount which I obviously should've replaced when I put in the new struts. They seemed smooth/fine when I replaced the struts but 5k miles later and one of them was no longer smooth.

Try bouncing the car and see if you can illicit the same noise. If you can then have someone else bounce the car while you try and pin point said noise.

Btw, how the heck do you have a '99 Subaru which looks cleaner underneath and less rust then a 1 year old subaru from southern ontario?!
Haha yeah I got lucky, my last OB was much more rusty and harder to work on. My guess is a lot of these components like the rotors/calipers and possibly other suspension parts were changed at some point, probably when he welded the last strut or changed the wheels. There are some rusty parts but I’m thankful it’s not too bad, i think the car spent a lot of time in forida too.

Strut mounts are brand new, bought them loaded/complete so I didnt reuse any old parts and because I also don’t have the tools to compress springs and reuse the old strut parts, I didn’t really want to anyone I just wanted brand new ones. I’m guessing something something is loose, it could possibly even be a brake/caliper part as I’ve heard it knock when not going over bumps, just coming to a stop and my tires bumping the curb.
Is everything torqued properly? I believe something loose would be about the only thing that could cause a strut to knock when going over a bump, unless there is some kind of defect in the strut itself.
Otherwise, with the pull, I would check the ball joints, they are good for making noise when done, and can cause some pull, but really with the pull, check the tie rods, and all related steering component bushings.
Yeah I don’t have a torque wrench but I’m going to grab one tomorrow and take the tire off and pull everything back off and torque all the bolts to correct specs. I’m guessing I also left something either loose or just not on straight enough. Ball joints and other suspension parts looked fine.

I notice the knock when taking a right turn and hitting the brakes and also when coming to a stop/hitting the brakes as my front tires touch the curb so I wonder if it’s a brake component making the noise. I’ll take my time and torque everything correctly next time and also try to find out where the knock is exactly coming from.
  • Like
Reactions: 1
After you solve your knock issue you will need to have an alignment done whenever you change MacPherson struts.
Yeah that’s on my list. I can hear the knock clearly coming from the right side, where the strap broke in the axle pulled out and made a grinding noise for a few feet, two times. The knock happens sometimes even when I’m just turning my car and not even really going over a bump, just turning it too fast and hard. I’m starting to wonder if it’s my axle that is damaged and it’s bouncing around/getting worse. The noise does seem to be getting a little bit worse so I’m gonna have to take everything apart and look at it hopefully tomorrow.
  • Like
Reactions: 1
Try rocking the car back and forth (left to right). If you can hear the knocking, check the swaybar links and bushings.
The thing is all those components were fine prior to putting on the new struts. I must have messed up somewhere, the axle was damaged when the strut broke, or the struts are making noise because they’re cheap Amazon parts. I’m gonna take a look at it today as the noise is slowly getting worse. The right side knocks on bumps, sometimes brakes and turning and the left crunches sometimes on bumps. It’s just super annoying, every time I fix something there always has to be another issue or it never goes smoothly and I have to force things into place.

The front passenger axle wasn’t in far enough so I had to take it back apart and get under the car, tank it into place and hold it tight there while someone pushed the knuckle onto the strut and put a bolt in. I’m suspecting something isn’t tightened on straight or correctly idk. I’m about to go out now and try to diagnose it and rip it apart for a third time.
  • Sad
Reactions: 1
Try rocking the car back and forth (left to right). If you can hear the knocking, check the swaybar links and bushings.
i figured it out, it was a loose pinch bolt on the passenger front knuckle. I loosened it when taking the knuckle off and forgot to tighten it. Knock has gone away since…

Time to figure out the other noises that randomly happen every other day now! Haha
  • Like
Reactions: 2
1 - 6 of 11 Posts