Rear Suspension Failure

[IrelandHS]

Hi
Hoping someone can give me a bit of advice on my rear suspension. 2015 model, UK model imported into Ireland. I underwent my NCT (National Car Testing requirment) test in January and the rear suspesion failed with a reading of 45Mm with imbalance of 33% (a pass is 30%). I went back to dealer and they replaced the rear suspension under warranty. Did the NCT retest and it failed again with exactly the same reading. The dealer took it back again and replaced the springs and they tested the suspension themselves and said they got 13%. Two weeks later I did another NCT and the rear suspension only just passed with a reading of 44Mm and 30%. I only just passed the test but to me there is obviously still a problem here. Has anyone had similar issues that have been resolved. I'm not very knowledgable when it comes to cars so I'm not sure what else can be done to fix the problem - anyone have any ideas? Any help/advice what be much appreciated.
Thanks
Harriet

 

[bobfromcork]

Hello Harriet
I've just failed my NCT with a 2015 Outlander imported from the UK - 20,000 miles on the clock. I had 34% imbalance on re suspension.
I'm dealing with Mitsubishi at the moment.
Not sure how it will turn out,
BOB

 

[IrelandHS]

Hi Bob

Since my post, I think there have been a few other cases, your car being one of them. At the time, my father-in-law, who works in motor parts said he'd heard there was a flaw with the 'bushing' "Bushings are cushions made of rubber, polyurethane (often shortened to “poly” or “urethane”) or other materials. They're mounted on car suspension and steering joints to absorb road bumps, control the amount of movement in the joints and reduce noise and vibration."

When I menitoned that to the Mitsubishi dealer, they said no.

But when I took the car in for a service this year in January 2020, I asked them again and they said that yes it was a problem with the Bushings on that make/model. They said they would replace them before my next NCT and they didn't need replacing during the service.

So I would definitely question them on this.

Hope this helps.

 

[Solargen]

Last year my 2015 developed a "thud" noise in the left rear suspension. The dealer said there was no issue, so I took it to my local garage and they found that a spacer on the top mounting of the shock absorber was badly distorted. It was replaced and the problem was fixed. I don't know whether that problem is widespread and if so might possibly be causing the problems you are having.

 

[michael8554]

I've never heard of suspension imbalance before, can someone explain please?

 

[jaapv]

Same here, explanation welcome.

 

[IrelandHS]

Hi

I can't work out how to insert an image so this is a quote from the NCT website who are the Vehicle roadworthy testing provider in Ireland.

"The suspension Test: The suspension test plates measure the movement of the suspension on each wheel and compares the readings for both wheels on a single axle (ie imbalance). The Suspension test Plates also record the weight at each wheel and sums all four measurements to give total vehicle weight"

It doesn't mean much to me but may mean more to others.
Cheers
Harriet

 

[Regulo]

From the Manual, the same test applies to the front suspension.
View attachment Screenshot (19).jpg

 

[jaapv]

A bit of googling did the rick:

This simply means you have one shock absorber worn more than another creating an imbalance, depending on the scale % of the imbalance depends on how much more worn it is ie,, 90% imbalance worn shock is a totaly ruined and 3% not to much to worry about but will need attention

Why can't they simply say: "worn shock absorber"? :?: :?:

 

[greendwarf]

The old fashioned way of checking is to "bounce" each corner of the car by pushing down hard and watching the rebound - useful when buying second-hand.

 

[IrelandHS]

Just be aware that I got the rear suspension and springs replaced and still got high imbalance reading. So just saying 'worn out shock absorber' does not take into account which part is worn out.

It turns out there is an issue with the Bushings in these cars I believe.

 

[bobfromcork]

If anyone els has had this problem I'd love to hear from you as I am dealing with it right now. Thanks to all for comments so far. I only got the car in January!
Keep well,
B

 

[jaapv]

Just be aware that I got the rear suspension and springs replaced and still got high imbalance reading. So just saying 'worn out shock absorber' does not take into account which part is worn out.

It turns out there is an issue with the Bushings in these cars I believe.

If you got the rear suspension and springs replaced without success that cannot have been the cause.

 

[IrelandHS]

Yes Mr Netherlands.
That's exactly what I'm trying to say. :shock:
The imbalance was caused by something other than the two main suspension parts! Which turns out to be the bushings.

 

[greendwarf]

The dealer thought it might be "worn springs" - since when has that ever been a thing?

So they put the car up, replace all the suspension and don't notice (or even suspect) the bushes?

Sound like cowboys to me :twisted:

 

[jaapv]

Cowboys - or fools... Since when does one replace a suspension without replacing bushes and rubbers?

 

[AndyInOz]

Cowboys - or fools... Since when does one replace a suspension without replacing bushes and rubbers?

I have to say, this was my first thought too.

Last time I had any suspension work done (different car) everything was supplied as a kit.

(The guys doing the fitting even showed me how the new bushes were an improvement over the original ones).

I'm still toying with the idea of having mine lifted slightly...

(for ease of access and improved ground clearance).

 

[IrelandHS]

Just to finish I will say that it was a reputable Mitsubishi Dealer and I wasn't charged for any of the replacement parts so they weren't trying to take money off me.
But I do think they were generally dismissive of the imbalance readings, wanting to blame the nct testing equipment and wanted to do the minimum to get the car over the line.

Now I just want other people to be aware of this weakness that is not uncommon in this model and to ensure the entire suspension is checked /replaced.

Thanks
Harriet

 

[jaapv]

Oh, they make money from a guaranty repair all right. It is just the factory being billed instead of you.
Did the car drive any differently after the repair?

 

[greendwarf]

Thinking more about this, I'm still alarmed at the "worn springs" suggestion. I've heard of "broken" springs but never "worn", as the physical nature of a spring is that it can only really become weakened by over-extension (impossible on a car) and never by excessive compression when acting as a shock absorber. Yes dampers do wear out and very occasionally so do bushes but I have only had this problem once in years of motoring. Given the general reluctance of Mitsu to repair anything under warranty I doubt the OP actually had the springs changed unless it is easier/cheaper to do this when replacing a faulty damper by putting in an entire new strut assembly.

As far as I can see from an example on ebay the car has trailing arm suspension with Macpherson struts which seem to involve a number of bushed joints - so difficult to know which are being referred to, but I don't recall anyone having this problem on this forum. Therefore, not sure that this can be described is a well known issue with the PHEV.