Cmax rear shocks

[Stilo]

Wifey's 05 Cmax failed its test yesterday due to a rear shocks imbalance. Just looked at it quickly before the rain hammered down and it seems that the top of the shock top mount bolts on from the outside. Am I right, and if so, does this mean that there's no dismantling done from inside the car?

[Karl]

Yep x2 10mm bolts accessible from under wheel arch

[Karl]

Your Irish mot sounds very strict

[Stilo]

Mar 29, 2015 12:26:25 GMT 1 Karl said:

Your Irish mot sounds very strict

There's only one reason for rejection here. Clearly leaking.

It is strict, yes! They bounce each wheel on a vibrating plate to measure shock travel. If the difference in travel between the shocks (imbalance) on each axle exceeds 30% then it's an automatic fail. The near side has 114mm and the offside 53mm, and the calculated imbalance is 54% and therefore a fail. Clearly the near side shock is duff but if the offside was equally as duff the it would pass provided there is no physical damage or leaks!!

[Karl]

www.motinfo.gov.uk/htdocs/m4s02000701.htm


We don't test there performance here

[dooroy]

The imbalance can often be down to worn bushings rather than any fault in the shocks themselves.
Problem is that its not possible to get the bushings on their own for passenger cars in general - you have to change the shocks .
Some motor factors are selling 'universal' bushings but they don't suit all cars.
Just 2 examples I had recently :
(DOE) 2007 Hiace rear shocks failed , 67% imbalance ; got bushings from Toyota - passes retest ;
(NCT) 2000 Galaxy rear shocks failed , 56% imbalace ; couldn't get bushings so fitted 2 new shocks ;
I removed the Galaxy shocks and both were dry and felt the same when pressure applied - but bushings were obviously worn .

[Stilo]

I'd say the difference between the two - being 63mm - wouldn't be the bush!! Looked at the shock close-up earlier and it does look damp when extended.

[dooroy]

Would tend to agree with you but the Hiace had an imbalance of 67% and passed after changing the lower bushings in the shock with the high reading ??
And I presume the DOE use the same testing method as the NCT - or do they ?
If you could halve the present imbalance it would pass.

[Stilo]

Mar 29, 2015 19:45:21 GMT 1 dooroy said:

Would tend to agree with you but the Hiace had an imbalance of 67% and passed after changing the lower bushings in the shock with the high reading ??
And I presume the DOE use the same testing method as the NCT - or do they ?
If you could halve the present imbalance it would pass.

The bushes are ok here. Bearing in mind that the car is 10 years old and has done almost 140,000 miles, and is driven daily over some of the sharpest road humps and potholes imaginable, I think it's done well to be still on its original shocks! New ones ordered and will be delivered tomorrow. Got them both for €80

[dooroy]

These shocks certainly lasted well - and I know what you mean about the roads .
And as you would expect the nearside gets more of a hammering than the offside .
Great value for the replacements

[Stilo]

Mar 30, 2015 23:10:20 GMT 1 dooroy said:

These shocks certainly lasted well - and I know what you mean about the roads .
And as you would expect the nearside gets more of a hammering than the offside .
Great value for the replacements

Yeah, got them from Micksgarage who are usually very expensive. Brand is called Optimal. They're a budget German make but enquiries suggest they are fine. Sachs or Monroes are nearly 3 times the price. No point in spending big on a car that will only be kept for another year or two.

[mbev51]

the french test checks the same.