306 rear suspension noise

I'm struggling with this one.

My old 99 306TD has about 150,000 miles on the clock. For about the last
year the rear suspension makes a loud clacking/clicking noise on occasion
when driving over bumps.

I've has the rear end up in the air and could not find anything wrong at
all. I tightened every bolt, but the problem persisted. The other day I
asked my mate who owns a garage and he said that it would be the suspension
mounts that live above the rear suspension cross tube. I got two today (£50
;-( ) and fitted them. The car is just the same! I'm at a loss as to what
could be the trouble - has anyone experienced this one before?

Julian.

 

Are you absolutely 100% sure that the noise is coming from the back? Before
you say "Yes, of course it is", just take a moment to check the antiroll bar
links on the front suspension. Any play in these will give symptoms you
describe and it also feeds them in through the floor of the car so the sound
travels around. BTDTGTTS

If it isn't that, there are four rubber mountings for the rear end, but I
think you have to drop the whole assembly to get at the other two.

Ron Robinson

 

What about your shockers they could be moving about from side to side
due to the rubber bushes gone,or up and down due to the rubber bushes
wear.

 

OK thanks. It's deffo the rear suspension, when I stood under the car and
lowered the rear end back down off my jacking beam (after replacing the
front pair of the rear bushes I got a lovely 'crack' sound from it - but
couldn't replicate it by raising and lowering the rear end. Take it for a
drive and you get it though!

Actually the front two needs the axle dropping - but only by a bit, you can
leave the ABS wires and brake pipes on.
The rear mounting bushes are dead easy, two bolts, one on top one below.

But I'm buggered if I know what this noise is. Maybe I might pull off the
dampers (bushes look good) and see if that stops the noise. Other than that
I wondered if the trailing arm bearings are knackered? But I've seen that on
205s before and the wheels start to lean in at the top, (negative camber!)
mine look fine.

Julian.

 

I had something like this a few years ago on a 405 diesel.

The bushes in the rear axle dry up and wear. They make a horrible
noise just like you describe. A clue is to look at the back wheels
from behind the car. If they'not upright and seem to tilt inward it's
a good sign the bushes are worn.

The easiest fix is to get hold of an axle and replace the whole lot.

Richard

 

Most 405 have a little tilt in on top of the wheels.

 

Well I still can't find the noise. I take your point about the rear axle
bearings (where the trailing arms fix to the cross tube) but this car has
only done about 150,000 miles and the wheels are still quite upright. I once
had an old 205 that covered 300,000 miles, the rear axle was well worn but
didn't make any noise.

This week I finally got around to replacing the brake servo, (it hissed all
the time) a horrid job really, but if you remove the top engine mount and
allow the engine to fall down and forward you can just get it out. Also I
treated it to new front pads because the old ones had started to rub on the
metal, and two new anti-roll bar drop arms.

I'm still mystified by this horrid noise, all the rubber joints look fine
and I've grollied up every bolt on the suspension/subframes etc really
tight!

Julian.

 

I know this sounds a horrible bodge, but when it happened to my 405 I
covered the area where the trailing arm meets the tube with grease. I
then heated it with a blowlamp to help it get into the bush and lo and
behold, it worked! For a while that is, beacuse the noise returned
after a couple of months. Still, it proved a point.

Richard

 

its not the exhaust knocking is it ,(i know it might be a Silly this to
ask)

 

OK I'll give that a try, there's nothing to loose. I wonder if some machine
oil would be better?

It's a real shame that Pug never put two grease nipples on the rear
suspension, if they had of then I bet they would never wear out.

Julian.