2005 WRX rear end knocking

[Smollet]

Recently I've been getting a knocking sound at low speed manoeuvring from the rear suspension and when stopping it's like the car is settling down. Any ideas ?

[red997]

same on the Mrs' WRX STi
just about to start investigating.
given it's mileage (115K) and the fact its had NO suspension work at all since new, I'm guessing:-

rear ARB links
probably all the rubber bushings
Strut bearing wear
anything else likely ?

[dennieboy96]

Heey, is it in the rear of your car? Than probarly your topmount common point of knocking on a wrx.

[Smollet]

Definitely in the rear. Only done 47k.

[vxr2010]

if it's a sti or similar suspension set up it's the shocks internally getting stuck , it's like a bumping worse in reverse and it seems to release in stages , if it is that it's very common , it's sort of curable if you regress the shocks or buy new suspension , if it's not that then have a good wobble of parts underneath and see what is loose , if it's suspension as i said my fsti was like that for years no issues , i ended up doing coilovers as i wanted better handling

[Konan]

The 2005 WRX has an inverted type shock like the STi, which do suffer early failures. Mine started with exactly those symptoms at just 30K miles.

If you jack that corner up and spray the shock with some lith grease around the point the shock slides into the body, you'll probably find it shuts up for 100 miles. If it does, the shock is starting to knock.

I rebuilt mine using 03 struts, not wanting to go through it all again in 30K. 05 top mounts will take an 03 shock (not earlier). Easy DIY job as there's no adjustment to disturb at the rear when taking the strut off.

[Smollet]

Finally got a new set of shocks from Sachs fitted by Surrey Subaru Specialists today. Amazing transformation. I didn't realise how far they'd actually deteriorated.

[Mr Taxpayer]

What Konan said. I have winter and summer wheels and when I swap them over I always lift the gaiter and spray lithium grease over exposed shock shaft. The cure is good for a few thousand miles.

It might be something else, but the treatment above costs £5 for a tin of grease and 15 minutes a corner to jack the car and remove the wheel. If it persists then at least you've ruled it out.