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Discussion Starter #1
The suspension on my 1991 3.6L car is really past its use by date.
although mileage is not high, I suspect the deterioration is time dependant - seals packing up, contamination etc.

I just priced new components with BMW as follows:
front set of replacement dampers
front damper stops
front rubber protection boots
rear set of sls replacement dampers
rear damper stops
rear rubber protection boots

all in, including VAT = 1500(GBP)

how does that compare to current aftermarket units, also to OEM prices in the UK, Europe and the North America?
 

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Replace the springs aswell, and topmounts.
 

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Discussion Starter #3 (Edited)
Why would the springs be a problem?
Car stance looks good, no sagging on any corners. Springs should not fail, given their cycle use is quite low?

Also, why the top mounts? How would these fail, and what should I look for?

Appreciate your input, S NL
 

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Springs are metal and 16 years old. The cope with the frequenting mass of a 1670 kg car every day. Low mileage or not, I'd replace.

Top mounts get severe beating on bad roads , i.e city streets. The steering feel and lightness usually improves seriously when replacing. Rear ones often corrode, although in your case thay may not be the case. However, worn rubber is probably present.

The thing with these issues is that, when an owner wants to replace shocks, the bill already is quite high including labour + alignment if needed, so they usually don't replace springs and topmounts, taking the chances of those still being the original factory ones quite high.

But, your car, your call!

Wout
 

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Why would the springs be a problem?
Car stance looks good, no sagging on any corners. Springs should not fail, given their cycle use is quite low?

Also, why the top mounts? How would these fail, and what should I look for?

Appreciate your input, S NL
Hi!
Springs: Metal fatigue, the car has had its weight on those springs, what 16 years now, there is a big risk for snapped coils. No point in saving on this.

Top mounts: Rear mounts are made of rubber, often a source for cloncks and other suspension related noises. Front top mounts can also be noisy, and as you are changing every other part in the suspension, it would be shame to have noises that yu get irritated over after all the work. Just preventive maintenance...:blabla:
Of course, it is your call. These kind of things tend to add up....

:cheers:
Sakke
 

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Springs are metal and 16 years old. The cope with the frequenting mass of a 1670 kg car every day. Low mileage or not, I'd replace.

Top mounts get severe beating on bad roads , i.e city streets. The steering feel and lightness usually improves seriously when replacing. Rear ones often corrode, although in your case thay may not be the case. However, worn rubber is probably present.

The thing with these issues is that, when an owner wants to replace shocks, the bill already is quite high including labour + alignment if needed, so they usually don't replace springs and topmounts, taking the chances of those still being the original factory ones quite high.

But, your car, your call!

Wout
Damn, you beat me to it....
:thumbsup:
Sakke
 

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Agree
I have changed many snapped springs on E34 M5.
2nd or 3rd coil down is favourite.
Front top mounts see huge shear load as well as compression.
On more than one occasion, removal of top mount will see spherical ball
race in mount fall to pieces.
 

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Discussion Starter #8
Springs snapping should be as a result of a fatigue failure. Fatigue will be directly proportional to the number of cycles of compression and rebound the springs have ensured.

Sure, excess corrosion pitting could generate stress concentration factors, but other wise the spring metal should not age while just standing around - other than slight sagging (memory loss) which is not evident in my cars case.
My theory anyway.

farrel, what sort of mileages had these failed springs seen?


On the top mount issue, I will definitely do a proper inspection of the units before reassemby. If there is any visible wear or deterioration I will order new parts. Might mean the car sits on jacks a little longer, but fortunately I have other modes of transport
 

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Springs snapping should be as a result of a fatigue failure. Fatigue will be directly proportional to the number of cycles of compression and rebound the springs have ensured.
that number is as high as it gets as they are probably the first ones still.

Sure, excess corrosion pitting could generate stress concentration factors, but other wise the spring metal should not age while just standing around - other than slight sagging (memory loss) which is not evident in my cars case.
My theory anyway.
Springs can fail whilst looking perfect. The actual breach in the metal always looks fresh upon inspection. I have seen failure on springs of similar quality in less than 7 years of age, lesser quality (mkI twingo, MKII Mondeo, MKII Stilo) can fail within 3 years.

The topmounts ofcourse require inspection, but its hard to feel a problem by hand that develops under load of the car. These are heavy-duty items. Wheelbearings can also appear perfect upon inspection yet still make so much noise you can clearly hear it.
 

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I greatly respect Farrell and Sebring's view on these matters and if I was spending the sort of Rand you are, the slight inconvenience of spending an extra 10% to replace parts that will have to be removed whilst fitting the other bits would be a 'no brainer'.

The fact is that the cost of springs and top mounts, compared to the cost of dampers, is tiny. Springs and top mounts will be out. The cost of fitting them will be minimal, if at all. But the cost of fitting again in 6, 12 18 months, will more than outweigh any savings you may achieve now by delaying replacement.

Good luck with it though. Great car!

Cheers
 
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