Rear suspension knock

[voxmagna]

MY12 Yeti 4WD TDi @ 50K has developed a dull 'thud' rear knock. I thought at first it was something in the boot or those polystyrene loose boxes. Notice it more with less fuel weight in the tank and have been trying to bring it on with slow speed violent turns to rock the suspension. It is definitely there. Weather is too wet to get a good look underneath on the ramps at the moment.

 

I'm suspecting bushes, shocks or exhaust. Are there any weaknesses on the rear or anything else to look at? Thanks

[Llanigraham]

Obvious one is to check the rear springs haven't broken.

Both of mine broke just over one full coil up from the bottom, however I didn't notice any noise from them.

[voxmagna]

Thanks, I have already had to replace a front spring on a VW, broken at the first coil. I had measured the arch heights and there was no difference or sag suggesting a broken spring. I will feel all around the coils and not be fooled this time.

 

Why are car springs breaking so much? I have had other older cars and whilst shocks were usually needed, I never had broken springs which seem common now. I had a discussion with a UK custom spring manufacturer who told me modern springs are made 'cold rolled', whereas they used to be hot formed. It sounds like it is all down to cheapness and premature failure built in. I came across another issue where the so called 'compatible' aftermarket spring was actually thinner than the OE. Now I will only buy an after market 'OE spec.' product and nothing like equivalent, compatible or other words.

 

I bet the old Landrover 110 springs never failed in 3-4 years!

 

 

[Llanigraham]

Thanks, I have already had to replace a front spring on a VW, broken at the first coil. I had measured the arch heights and there was no difference or sag suggesting a broken spring. I will feel all around the coils and not be fooled this time.

 

Why are car springs breaking so much? I have had other older cars and whilst shocks were usually needed, I never had broken springs which seem common now. I had a discussion with a UK custom spring manufacturer who told me modern springs are made 'cold rolled', whereas they used to be hot formed. It sounds like it is all down to cheapness and premature failure built in. I came across another issue where the so called 'compatible' aftermarket spring was actually thinner than the OE. Now I will only buy an after market 'OE spec.' product and nothing like equivalent, compatible or other words.

 

I bet the old Landrover 110 springs never failed in 3-4 years!

 

Mine didn't appear to have sagged and you could not see the breaks until it was in the air. The garage that replaced mine said they are replacing a couple of sets a week, across all makes, and put it down to crap roads and speed humps. They reckon the worst are Citroen!

[Ryeman]

Anyone would think the car was a new invention and we were just in the first stages of development.

I can't recall a report of a spring failure in Oz for many decades, other than outback corrugated desert roads carrying heavy loads at speed for hours.

[ejstubbs]

Why are car springs breaking so much? I have had other older cars and whilst shocks were usually needed, I never had broken springs which seem common now. I had a discussion with a UK custom spring manufacturer who told me modern springs are made 'cold rolled', whereas they used to be hot formed. It sounds like it is all down to cheapness and premature failure built in. I came across another issue where the so called 'compatible' aftermarket spring was actually thinner than the OE. Now I will only buy an after market 'OE spec.' product and nothing like equivalent, compatible or other words.

 

The AA published an online article about this back in 2012: http://www.theaa.com/motoring_advice/car-servicing-repair/coil-springs-breaking.html

 

Their view was that reducing the weight of the coil springs (reducing the overall weight of the car being one of the best ways to reduce fuel consumption) leaves less safety margin on loading.  Couple that with the general deterioration in the quality of road surfaces, add in the continued use of salt as a de-icer in winter and that's probably sufficient to explain the widely-observed rise in coil spring failures.

 

P.S. Anyone who attempts to blame the use of "recycled steel" is talking through their hat.  Iron and steel manufacture has used a percentage of scrap as a source material for centuries.  So long as the finished material meets the specification required for the intended use, it matters not a jot where the Fe atoms originate from.

[Ootohere]

As the cars get older, the consumables are going to possibly need replacing.  Coil springs are consumables now.

The same old just keeps happening.

http://briskoda.net/forums/topic/299236-broken-rear-coil-spring

http://briskoda.net/forums/topic/262559-yeti-mot-fail

Edited 14 February, 2016 by GoneOffskiroottoot

[muddyboots]

Mine (170 4x4, 2011, 60k miles) has also recently developed an occasional dull thud. At the moment I haven't been able to identify what triggers it.

From the driver's seat, it sounds like it's coming from over my right shoulder, kind of from the rear passenger door area - but I guess just below here is where the bushings are, or at least the trailing arm bush.

[wiilydog]

Its worth checking rear arb drop links too

[voxmagna]

Thanks, I just posted a design issue for the front ARB drop links and will be giving the rears the same microscopic examination.

[Big Rich]

Mine had the rear bump stops replaced yesterday and now on the Drivers side rear when driving over rough ground or over sleeping policemen I get what can best be described as a crash like a box of stones bouncing in the boot. The boot is empty and everything is tied down.

 

Any ideas as to what could have caused this and where to look as I've only 10 days left on the lease before I buy her and I want to get anything expensive replaced before the end.

 

From reading above it looks like it could be bushes related.

 

 

Thanks 

[Brijo]

Broken spring looks to be a good candidate?  It wouldn't be the first (ask Graham!).

Edited 29 February, 2016 by Brijo

[Llanigraham]

True!

However I got no noises from mine and was surprised when the MoT station failed the car because of them, as i did not know they were broken.

Car has now done 102k miles and is still very quiet.

[Big Rich]

Well she's in Furrows at Oswestry for them to find the culprit. Up to them replacing the bump stops it was perfectly quiet, to drive it you'd be hard pressed to realise that she'd clocked over 100k.

Just hoping they find the fault and fix it for me.

[Ryeman]

Have you eliminated dampers as a problem?.

[muddyboots]

Was underneath looking at mine the other day.

Most of the bushes I could see looked fine, with the exception of the inner bushes of both upper control arms.

I couldn't get enough angle to see "into" the bush, but what I could see was very freshly polished gloss black rubber, whereas all other bushes were the usual grey/weathered/dusty appearance.

To me that suggests they are both shot and are moving excessively.

Not sure if that's what causes my thud though; it *sounds* more like that noise comes from the top mount on the rear driver's side damper.

It's part 15 on this image:

http://vagfans.info/EN/skoda/CZ/YET/Yeti/2011/666/R/505/505030/wishbone-axle-guide-wheel-bearing-housing

(The inner bush of the arm shaped a bit like a question mark...)

So along with the knackered bump stops (going crumbly and falling to bits) and tired dampers, I can see myself doing a bit of work before long.

Edited 2 March, 2016 by muddyboots

[voxmagna]

I share your pain because there are so many parts and X2. Unless it is something I  discovered you can go straight to (ARB not clamping up to ball joint) there are few alternatives except pull the joints bushes/shock apart and look. In my case, the bad front knock was 12mm in a 12.5mm oversize hole metal to metal which doesn't seem a lot for the noise produced. Suspension parts can 'look' o.k under tension when there is wear. The only consolation is working on the rear is a lot easier than the front.

 

Broken springs seem very common on a lot of vags now, carefully feel all the way around the coils from top to bottom. A broken bottom half coil may look o.k at a quick glance. I've not had to pull our Yeti rear suspension apart yet, but another annoying issue on older vags causing noise was their design of the 'spring locating plate' . Early versions were plain steel then later they rubberized them. When I found this on a VW I cut a thin nitrile rubber spacer gasket for the spring support cup to sit on, isolating it from the chassis. When you eventually find the problem and test the fix over speed bumps, it will be like you just got a new car.

[Big Rich]

Good news she's fixed. was simply the case that the shock absorber wasn't sitting square in it's holder causing it to rattle. They have re-seated it and now she's quiet and back to her own self.

[muddyboots]

Good news she's fixed. was simply the case that the shock absorber wasn't sitting square in it's holder causing it to rattle. They have re-seated it and now she's quiet and back to her own self.

That's good to hear. I'm not quite sure how you fit them "not sitting square though".

Reminds me of when a Seat main dealer changed my front struts and managed to reassemble them with no top bearing fitted....

[clairelen]

I bought a 2L diesel 4WD 2015 Yeti in December, with mileage 18,400. From the start there were worrying loud thumps from the rear suspension when slowly traversing bumps. I thought this was just due to a stiff suspension. Having read Forum comments on this topic I'm not so sure. Any suggestions?

[Ryeman]

Broken spring would be my first thought 

[Llanigraham]

5 hours ago, clairelen said:

I bought a 2L diesel 4WD 2015 Yeti in December, with mileage 18,400. From the start there were worrying loud thumps from the rear suspension when slowly traversing bumps. I thought this was just due to a stiff suspension. Having read Forum comments on this topic I'm not so sure. Any suggestions?

It's under warranty, so if you are concerned take it back and get them to look at it.