bigmac

Whenever my car is loaded (ie 4-up), I get a load knocking noise (as if you were to bang you knuckles quickly on a wooden table - seriously that's what it sounds like).

The noise comes from the rear end of the car.

I also hear it, but much quieter, when it is just me in the car and when I go around a right hand bend (ie roundabouts).

Local garage is looking into it today, but so far nothing. So far they have checked the anti-roll bar (brushes) and the suspension - all are sound.

It's an STi V4 - 4 door.

Any ideas would be very welcome.

thanks, Mark.

bigmac

Jury is back.

It's my CD (Constant Drive Joint) or CV (Constant Velocity Joint) joint - not sure what the bloke said exactly.

Apparently there is a joint at the end of the driveshaft (guess this means my post is in the wrong forum too) that connects the driveshaft to the rear axles. Apparently, it's starting to go.

Now waiting for a part price...

submannz

It is the rear suspension top hats, the bushes flog out quickly more so if you have uprated the springs or struts. You will need to get the top hats replaced or I sent mine in to a suspension shop who replaced these with nolathane bushes.

Dan

LeoneTurbo

CV joints hardly wear out. My guess would be to much clearance on top or lower sping seats.

Neanderthal

iTrader: (6)

Mines developed this type of sound

It started to happen after I had to go a little off road over some very bumpy grass whilst making progress down a a single lane track

Tyres Northants had a quick look at the rear suspension when it was in for some new rear brakes. They couldn't see anything immediately wrong with the car.
As the car still handles the way it's always done I just ignore it when it occurs.

Funny thing is, I had exactly the same noise in my Calibra. They thought it was the baffles in the exhaust?

Matt

AlexM

Do you have an aftermarket exhaust?

My SS backbox was rubbing against the diff hanger when going around right hand corners.. adjusted the exhaust hangers and it was fixed!.

Try wiggling the back box around to see if you can get it to hit something.

Cheers,

Alex

Neanderthal

iTrader: (6)

Mine started doing it with the standard exhaust and it still does it now with my P1 backbox

Matt

bigmac

I have got a Scoobysport back end, but it's been on the car for a while (since Oct 1999). The noise has only started in the last 2-3 months.

Still waiting for a part price from Hendrys...

M4

If you lose an exhaust mounting it might start banging even if it didn't do it before.

M4

AlexM

My SS backbox was fitted for about a year before it started knocking... I think the rubber hangers stretch, or the mountings bend. Anyway, the clearences are a bit tight so it's worth checking.

Cheers,

A.

bigmac

excellent, I'll have a butchers at the weekend and see if that's the prob. If it is, it begs the question of why the garage didn't spot it!

regards, Mark.

Neanderthal

iTrader: (6)

I'll check mine to. What with this and the rattley gear stick my cars a veritable hive of mysterious sounds

Matt

bigmac

anyone who has had the SS backbox as the cause, can they confirm the following: -

Q) can it be related to the number of passengers in the car? (ie 4 up = lots of banging noise, only me in the car = very faint and only when going around right hand bends).

cheers, Mark.

Neanderthal

iTrader: (6)

The knocking noise I hear occurs a a slow steady speed, loudest if I'm going down hill off power.

These symtomes would leave me to believe it's the exhaust knocking around. It's going into Tyres Northampton on Thursday so I'm making a list of things I want them to look at (and thanks to Scoobynet, possible causes for said noises).

Will let you know!

Matt

submannz

Trust me it is your rear top hat bushes.

Kippax

submannz could be right. if you take your back seat out you can see the top of the strut either side. get someone else to drive the car round a car park and put your ear near the top of the strut. also put your fingers on it and it moves about especially if you got shorter springs on with standard shocks. even on standard springs as they get older they get shorter and rattle about a bit, more so when you are slowing down. when you accelerate, the weight shifts to the back of the car and compresses the clearance out thats why you cant hear it.