How to Tell if Rear Coil Springs gone Bad?

How to Tell if Rear Coil Springs gone Bad?

Author
Discussion

zakmuh

Original Poster:

454 posts

109 months

Monday 1st May 2017
quotequote all
Hi,

I recently bought a 2003 Kia Sorento (with normal shocks - not SLS). While on small road humps and pot holes, It's rear side has more rough ride (rear passenger gets hip pain!!) . It jumps and lands, not smooth, hits back so hard. It feels like the wheels are directly fixed to the chassis without a suspension system.

Is this the sign of worn coils?

Many thanks in advance smile

HustleRussell

24,602 posts

159 months

Monday 1st May 2017
quotequote all
More likely dampers.

Springs do sag over time but unless they're broken you won't get the pronounced symptoms you have.

GreenV8S

30,150 posts

283 months

Tuesday 2nd May 2017
quotequote all
HustleRussell said:
More likely dampers.
I agree.

E-bmw

9,106 posts

151 months

Tuesday 2nd May 2017
quotequote all
GreenV8S said:
HustleRussell said:
More likely dampers.
I agree.
+2, what you describe is a completely un-damped wheel.

zakmuh

Original Poster:

454 posts

109 months

Tuesday 2nd May 2017
quotequote all

Thanks all smile

So damper is the one moving the chassis up and down smoothly over dips and bumps and the coil springs help it to go back to right level?

I'll get it both of them checked and replaced over the weekend.

Cheers

CrutyRammers

13,735 posts

197 months

Tuesday 2nd May 2017
quotequote all
No, the spring absorbs the impact of bumps and pushes the wheel down into dips. The damper stops it from then bouncing up and down.

HustleRussell

24,602 posts

159 months

Tuesday 2nd May 2017
quotequote all
The springs support the car and the shock absorbers control the springs. If the dampers fail there is nothing to control the compression or rebound of the spring meaning that big bumps can easily fully compress the spring and you'll hit the bump stops making it feel as though you basically have no suspension. In normal driving the uncontrolled springs will also cause a bouncy and nauseating ride for rear passengers.

zakmuh

Original Poster:

454 posts

109 months

Tuesday 2nd May 2017
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Very well explained guys!

Thank you very much

Classy6

419 posts

176 months

Wednesday 3rd May 2017
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Easy way to check dampers, open the door and get someone heavy to jump up and down on the sill. Car should go down, up and then down to rest. A worn damper will just bounce up and down as you're describing.

PaulKemp

979 posts

144 months

Wednesday 3rd May 2017
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Always replace in pairs
But you new that right?

zakmuh

Original Poster:

454 posts

109 months

Wednesday 3rd May 2017
quotequote all
Thanks! The current shocks are KYB gas ones - some pics below.

Back of the car isn't bouncing excessively - no bouncing at all! I don't think if the worn upper/lower suspension arms contributing anything to cause those problems, along with the bad shocks?

Yes, the pair. I gave a bell to the car dealer from where I got the car from and he has agreed to replace them both + the leaking fuel tank.






HustleRussell

24,602 posts

159 months

Wednesday 3rd May 2017
quotequote all
I imagine it has a pretty basic trailing arm rear suspension so there's not much to go wrong there however if the rear subframe mounting bushes are gone that will produce a noticeable metal-on-metal knock. It won't cause the very bad ride you're describing though.

KYB are an aftermarket brand IIRC, I'm not sure if they're any good- being that they aren't factory there is always the chance that the wrong shocks have been fitted in the past.

If the rear ride height looks OK and equal both sides then prime suspect must be the shock absorbers.

Edited by HustleRussell on Wednesday 3rd May 10:40

paul.deitch

2,086 posts

256 months

Wednesday 3rd May 2017
quotequote all
I have the same car, same problem. Definitely dampers. Replace in pairs. The fronts are probably shot too so do them as well if the car dips on braking. Top nuts on rears were really rusted...

zakmuh

Original Poster:

454 posts

109 months

Wednesday 3rd May 2017
quotequote all
No knocking noise from anywhere. I checked all the bushes with a pry bar and its all good. Peddders ( http://www.pedders.co.uk/kia-sorento-20022007-rear... ) do SLS to normal shocks conversion. From there website I checked the wheel-to-wheel arch measurement, which is 720mmm and its correct on mine.

Yes, its rusting heavily but luckily metal isn't falling off yet. I have to give to car washers to do a thorough underbody wash and then Waxoyl treatment. And do this again just before the winter. Some local garages do this for cars. I hope this treatment will control/minimise rusting further? Full underbody coating will cost me circa £1300!


zakmuh

Original Poster:

454 posts

109 months

Thursday 4th May 2017
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paul.deitch said:
I have the same car, same problem. Definitely dampers. Replace in pairs. The fronts are probably shot too so do them as well if the car dips on braking. Top nuts on rears were really rusted...
Paul, was yours sorted after replacing both rear dampers, no more bouncy ride at the back? I guess yours is XS model as well, so was it normal shocks or or SLS?

Cheers

paul.deitch

2,086 posts

256 months

Thursday 4th May 2017
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Yes absolutely normal now. Wish I had done it a year ago as it didn't help my wife's back hitting gigantic speed humps in Portugal last summer. Got to admit that the hammer blow surprised me as well and stopped to check that the car wasn't totally f-ed.
Yes standard suspension and automatic. Doing the fronts as well made it feel more secure when cornering and stopping. I'm running M+S/ W+S tyres as I'm living in Germany and can't be bothered with the annual hassle of changing.

Previous owner was either a farmer or off-roader as the tank guard is BENT and the underside was/is still full of earth and there are scratches all over. MOT/TUV next week so we'll see...
Love it although it is a bit juicy.

zakmuh

Original Poster:

454 posts

109 months

Thursday 4th May 2017
quotequote all
Glad to hear all sorted. May I ask , whats that ' I'm running M+S/ W+S tyres'? Mine has 70 think tyres. I dont't think part worn ones are that expensive?

My underbody has loads and loads rusting. I'm gonna give it a Waxoyl treatment. I have disabled the TCCS power supply (2WD conversion) so it's okay on mileage smile


paul.deitch

2,086 posts

256 months

Thursday 4th May 2017
quotequote all
W+S is winter/summer or all year tyres. I think on my model I just have to remove the fuse to disable 4 wheel drive. May be next week when I sort out why the rear defrost does't work. The UK Kia forum is very good for help on most things.

zakmuh

Original Poster:

454 posts

109 months

Friday 5th May 2017
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Thanks.

Lots of interior lights aren't working on mine either, especially the dashboard clock and front hood light. I just need to spend whole weekend to get to the bottom of it and sort everything out. Yes, this forum, is a life saves!

Edited by zakmuh on Monday 8th May 08:06

Stickyfinger

8,429 posts

104 months

Friday 5th May 2017
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I would look at getting that car rust treated/waxed as well !