Rear Knock Developed @ 7,000mi
 

I've been hearing a pretty noticeable knock/pop/crack sound from my passenger-side rear corner for a month or so now.

It started around 7,000mi, so I brought the car in to Capitol Subaru service, they did a quick inspection and test drive, and found nothing. (I got back in the car and the radio was on, were they listening for the noise or just cruising in my car?)

A few weeks later, I brought the car to Stevens Creek service (wayyy better service here, as I'll soon discover) for my 7,500mi appointment. I had them do another check and they discovered the sway bar link nut was loose by about 3 full turns.

Well... turns out that wasn't the problem. I let two weeks go by, and now the knock happens over any uneven road surface at any speed. (video link below) I brought the car back to Stevens Creek this morning and the service manager took the car for a spin, he heard it immediately. They said the car isn't safe to drive and gave me a 2015 Forester loaner. I'll keep you all updated!

[ame="https://www.youtube.com/watch?v=QAujlh1eNWg"]BRZ Knocking Sound - YouTube[/ame]

Yes, please do.

Did they say what they suspected was making that sound .. ??

humfrz

that definitely doesnt sound good

They said it sounds like part of the structure in the strut tower may have failed, possibly a weld. My car is totally stock.

Well, then .... that ought to fix up so it's good as new .... :thumbsup:


humfrz

That sucks. Mine had a knock on the passenger-side rear for a while when I would cruise at 70+mph. Turned out to be my oem spoiler was flapping around. The double-sided tape had let go.

That sounds like the frame is falling apart. :O

It doesn't sound good at all... interested to know what it is.

Technically the rear shocks aren't struts, it's just a shock so it takes no lateral loads.

I'm having a hard time deciphering what noise you're talking about in the video, is it the higher pitch pop/click (heard from 5-9sec and again at 20sec) or the lower pitch thunk/groan sound heard from 9-12sec?

The noise could be from the shock assembly itself, or any of the suspension components, or it could be the rear deck pop/noise many members had a while back.
http://www.ft86club.com/forums/showt...r+deck+popping

My frs drivers side shock went bad around 5k miles replaced under warranty. I had that same noise drove me nuts

Just got my car back. The service team said they had found popping coming from several sources and "adjusted several weld areas and lubricated". Driving home, I heard nothing. I'll let you all know if it comes back.

You can hear it twice pretty clearly at 10 and 11 seconds, its a high pitch pop.

What does "adjusted several weld areas" mean? They rewelded something?

probably bent, er, I mean "tweaked" something...

.....:lol: ....... most likely with a big hammer, then squirted some WD-40 around the area ..... ;)


humfrz

Haha... I was wondering the same thing, and those are the exact words on the invoice. I picked the car up after service hours, so I didn't get to talk in detail with an advisor. Whatever they did, the noise is now gone.

Well, 10 days later, and it's back. It was really prominent yesterday when the temperature hit the high 90s. I just dropped off the car again at Stevens Creek Subaru, so I'll update when/what I hear back. I'm starting to like this Forester loaner car they've been giving me, haha.

On the plus side, they're also installing my new OZ Ultraleggera's that I ordered from Tire Rack. :D

Have that too - Try running with the rear seat down. I believe it is the rear seat latch - have not the time to take apart a rear seat yet <--lazy

I thought that was the issue at the beginning, but this is much louder, and it's definitely coming from the structure. I had all 4 of my new wheels in the car on Thursday when bringing it to the dealership, so the seats were down, and I still had the noise. The service manager is working on the car himself, and asked to keep it for the whole weekend. We'll see what happens...

Well, I just picked up the car, and nothing new. I'm gonna drive on it for a few weeks to see what happens.

Hopefully they used a bigger hammer for the adjustments this time

Update! Brought the car back last week... FOURTH time. They still have it and it's been 7 days, by far the longest they've worked on it. I went in today to get an update, and they happened to be working on it when I got there, so I got a look at what they were doing.

Apparently, the anti-corrosive paint that the whole body gets submerged in fills in the gaps between the two welded panels in the rear where the snapping sound is coming from. The combination of the gap and the paint in-between is apparently making this noise. Their solution is to strip back this layer and lubricate the gap. I'm not entirely convinced that excess paint in a gap can create this loud of a sound. However, the amount of work they've been putting into this, hopefully they know what they're doing. I should get the car back tomorrow, hopefully without issue this time. Fingers crossed.