Subaru knocking

[Luke.]

I've recently bought an Outback and when I reverse on full lock there's a fairly quiet knocking or clicking sound.

I'm also reversing up a slight gradient, and it happens first thing in the morning usually when the engine's cold. Not sure this makes any difference, but just thought I'd mention it.

Underway, there's no knocking to be heard.

Anyone got any clues as to what it might be?

[Steve_W]

When my Impreza did that it turned out to be the anti-roll bar and front subframe nuts not being torqued up properly.

My car doesn't go to that garage anymore!

[The Wookie]

Could be a CV joint, but I had similar symptoms on my old Evo caused by knackered top mounts

[Luke.]

The Wookie said:

Could be a CV joint, but I had similar symptoms on my old Evo caused by knackered top mounts

I'm a bit mechanically rubbish - are CV joints expensive to replace?

[E30M3SE]

Reversing with full lock? Could just be one of the differentials, and nothing to be concerned about.

[Luke.]

E30M3SE said:

Reversing with full lock? Could just be one of the differentials.

Is that bad? Sounds bad. But the way you've written it, sounds not so bad.

[E30M3SE]

My M3 has an LSD, and when reversing off a drive, with lots or full lock of manuvering slowing in a tight car park for example, the diff can be 'felt working'.

Not sure what type of diffs an Outback has, just thinking along the same lines, if the diff had issues then surely you would hear it knocking and clicking on the move also.

Edited by E30M3SE on Thursday 10th February 11:57

[JM]

Might be worth checkin oil levels in diffs etc, and probably changing it.

Try reversing in and driving out of the space.

[Luke.]

Cheers all. Sounds like it could be a few different things. Will get a mobile mechanic out.

[Luke.]

After a little more reading around on the internet. It seems its most likely a 'feature' of the four wheel drive system and just the diffs doing their stuff.

Happy days, I think.

[Luke.]

hora said:

My Forester and Legacy never did this.

Personally I'd get it up on a ramp at an indie and get them wiggling/checking.

Who did you buy the car from?

Bought it from a small independent trader up near Malvern. So basically miles away from me.

Would it make a difference that it happens when I'm reversing on full lock up a small slope? Probably clutching at straws here though.

But reading around the various Subaru forums I did kind of get a feeling of TADTS.

Edited to add - it kind of feels like I've run over a stick.

[Luke.]

Where you reversing your Legacy/Forester on the flat or up a gradient?

[Luke.]

hora said:

All varieties. Not once.

Call your local main dealer service dept- ask to be put through and describe. its worth checking out (even if its £70 diagnostic) just for peace of mind.

I just called them, but were pretty vague and said just bring the car in. But can't get it to them for a week or so.

Though reassuringly someone in another forum gets exactly this on his STi and said he's not bothered about it.

[Luke.]

I know, but up to my eyes in a house move and various other odds and s0ds, so will keep an eye on the car and address it when I've got a little more time.

[ffc]

I had this on my Legacy tourer, it was a symptom of tyre wear on the front tyres. As i reversed on full lock I would experience a bumping/knocking sound from the front end. New tyres always cleared the problem. I had the car five years and this always happened when the tyres were worn.