off-side suspension knock

stew81 · #1 02-01-10

when bringing the clutch up to move away slowly (either forward or reverse) you can hear a light clonk/knock from the lower suspension on the drivers side, it doesnt do it once the car is moving only at move off. any ideas? On a maybe related note the car seems to be understeering horribly at the moment (today i almost ended up in the next lane when turning left) and when driving down a straight i can wiggle the steering wheel a good 2 inches side to side without it having any impact on the direction of the car

i dont actually feel too confident driving it at the moment..which is annoying as im back in the work van from monday and then ill barely get any opportunities to take the saab for a spin!

c900 · #2 02-01-10

Might be that the butterfly bush on the affected side (it's the rear bush on the control arm) has gone. Can you jack up the car, take the wheel off and sit there to have a good look at everything?

Craig.

stew81 · #3 02-01-10

thanks for the suggestion craig. Im planning on replacing those with poly anyway so i wouldnt be too dissapointed if it was the rear butterfly bush.

Bitter and Twisted !!! · #4 03-01-10

Yeah i'd have gone for butterfly bushes too

c900 · #5 03-01-10

Quote:

Originally Posted by stew81

thanks for the suggestion craig. Im planning on replacing those with poly anyway so i wouldnt be too dissapointed if it was the rear butterfly bush.

Ok if you're planning to go poly for the butterfly bushes, what I did when I replaced the ones on my car was buy the powerflex bushes and 'blank' bush housings which the UK competitor to PFS that we're not allowed to mention here sells (but PFS doesn't).

That way you get brand new aluminium bush housings and the powerflex bushes fit straight in. There is a very good guide to renewing thoses bushes on saab9000.com which I recommend. When you are exploring the butterfly bush theory, check the ball joints for wear too. They are easy to replace if you need to renew them.

My car's renewed suspension will get tested as soon as I get something to replace the dodgy brake light switch, but I'm sure it'll be much better than it was before.

Craig.

mick44 · #6 03-01-10

personally i would go for the lower ball joint on whatever side your getting the knock from, easy to diagnose easy to fix and only cost you about a tenner!

Bitter and Twisted !!! · #7 03-01-10

A ball joint would also give you the same symptoms as you described and as Mick44 points out they're reasonably cheap and easy to fit so its worth checking these out aswell before buying anything.

stew81 · #8 03-01-10

cheers guys. would the ball joint not be constantly knocking while driving if it was knackered though? at the moment its only really evident whilst manouvering the car slowly! maybe because the knock is so quiet i dont here it over the other road noise once travelling at speed?

btw, the car had its MOT 3 weeks ago, passed with flying colours! i would have hoped the test centre would have picked up on worn suspension components!

stew81 · #9 03-01-10

i took the car down to an empty carpark to see under what conditions i could get it to make the sound.
the best method i found was crawling along in first and then blibing the accelerator so the car jerks forward (or driving like a learner as its otherwise known

), everytime i done this i got the knocking sound.
think im gonna have a general blitz on the front end and do both balljoints and both track-rod ends when i get the poly's for the butterfly bush.

this problems really taken the gloss off the glee i was feeling after getting a maptun strut brace for christmas!