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My 2005 Jetta TDI Wagon started making a "spring like sound" that was coming from the right rear corner - I pulled the wheel and found this:

Broken spring and twisted bumper

Piece that broke off of the top of the spring

I'm trying to decide if I need to "ground" the car or if it can be safely driven while I wait for parts to arrive. I figure I should replace both springs, their bumpers, and since I'm there also replace the shocks (they are probably original with 200,000+ miles on them).

Given the mileage - and the work it will take to replace the spring - is there anything else that I should be looking at / replacing? I assume it would be wisest to replace both springs.

dlu
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    You are right to replace the shocks as well, if the spring is broken the shock will be bearing far more weight than it's designed for. – GdD Feb 03 '20 at 10:26
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    @GdD Shocks don't bear weight, they just add resistance to movement. As long as the suspension rubber buffers are intact which limit suspension maximum travel, then there should no damage to the shocks. – HandyHowie Feb 03 '20 at 11:25
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    I don't quite agree with that @HandyHowie, the shocks don't bear weight in normal circumstances, but a broken spring isn't normal. Replacing the shocks is a good call. – GdD Feb 03 '20 at 11:27
  • The OP needs to inspect that shock - if there is any scraping damage then it needs replacing. – Solar Mike Feb 03 '20 at 15:38
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    The failure is hydrogen stress cracking ; could be caused by coating failure permitting corrosion, but more likely a manufacturing defect in the steel which concentrated stresses and hydrogen. I would replace both rear springs. It has nothing to do with the shocks but because of the mileage , I would replace the shocks at the same time. – blacksmith37 Feb 03 '20 at 15:41
  • @HandyHowie - Thanks, understand that the shocks don't bear weight. The secondary question is two part: what else might have been damaged? And, what else is likely to be sufficiently worn / near end-of-life that it would be worth replacing at the same time? – dlu Feb 03 '20 at 16:33
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    @dlu If nothing else looks damaged, I wouldn’t do anything else. It does look like it would be a simple job to remove the shocks, so if I was doing the job I would probably test the shocks off the car make sure they are working and if ok, I would put them back on. – HandyHowie Feb 03 '20 at 18:35
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    Here is a very similar question, does this help? https://mechanics.stackexchange.com/questions/69438/suspension-spring-coil-snapped-at-bottom-is-it-safe-to-drive-short-distance – dwizum Feb 03 '20 at 19:42
  • I am voting to close this question as it appears to be the same in substance as the question @dwizum is referencing. – kyle_engineer Feb 03 '20 at 23:25
  • The spring broke because the upper spring perch has broken off of the body or vice versa), you have 2 repairs to make. – Moab Feb 04 '20 at 01:29
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    @moab If you look at the photo carefully, you will see that the upper spring mount is still in place, it is just the rubber that has pulled off the mount. – HandyHowie Feb 04 '20 at 10:58
  • While you're at it, I'd check the other springs and shocks as well. Good chance you better replace them all at once, or you'll be in the same situation again within 10k km. – Mast Feb 04 '20 at 12:29
  • @HandyHowie i Did, then why is it at a 45 degree angle. 1st image. – Moab Feb 04 '20 at 13:39
  • @moab It is only the rubber that is at 45 degrees. You can just see the metal mount holding back the spring on the right hand side. If you increase the brightness it is more visible. – HandyHowie Feb 04 '20 at 13:48
  • The mount appears to be ok, but the rubber bumper is sitting at that angle because the load for the spring changed when the tail broke off - all of the pressure is now on the outside. The tail used to wrap around the bumper. – dlu Feb 04 '20 at 17:50

6 Answers6

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That spring can rotate and rip out the tire - catastrophic loss when entering a bend could mean driver, occupants, other drivers, and/or bystanders could be singing with the angels...

Ground the car instantly, it is not safe.

Dan C
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Solar Mike
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My biggest concern with issues like this is causing additional damage since the spring is no longer being supported the way it was designed to be.

Also, the rear suspension is (obviously) compromised, handling is going to be affected.

My recommendation is to park it until it can be fixed.

jwh20
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The basic issue from a mechanical point of view is that the spring (not the shock!) is what supports the weight of that corner of the car. Clearly, with a piece missing, it is not doing that as it was designed to.

If the car "bounces" while being driven, the broken spring may end up further out of position and not carrying any load at all.

Personally I wouldn't drive it anywhere at more than walking pace, and avoid anything like driving up and down a kerb.

alephzero
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The last three quarters of a turn of the spring is flat, and coiled to a smaller diameter than the body of the spring, so that it can sit snugly around the locating nub welded onto the frame, with the rubber isolator between them. With most of the last turn missing, the spring is effectively resting on a single point. The first picture shows its proper position - you can just see a rusty circle behind the isolator that has also rolled out of position. Were the spring and isolator on that pad before you lifted it? You probably can't tell now, but the risk is that the spring becomes free to move out of position, and potentially fall out, or worse, fall towards the tire and rip it. Tyipcally, the limit of extension of the shock is intended to make sure that the spring doesn't come loose even under full travel, there's no guarantee of that now.

Al that was preventing the spring from moving any further was the now larger next coil of the spring, which was probably rubbing against the nub, and producing the sound you heard. You'd likely be challenged to even lower the car back onto its suspension with the spring returning to its proper location, but there's no guarantee it'd stay there.

I'd park that vehicle until you can get a new spring. It's just not worth the risk of using it.

Phil G
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Time to hit your pull-a-part junkyards, mayhaps with family members needing supplemental income =)
Some old-school places have people to do the pulls
(& even the replacement work) for you.

TeslaCoils
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Is it spring or the strut-mount assembly which is broken !!

The spring coil is placed with the rubber (and ball-bearing, if rear) kit on this mount. please confirm if the steel spring is broken or just this mount assembly?

However, if you don't change the broken coil, it would spoil shocks system on the other sides too.

user30612
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