Suspension Issues

[Ilya]

Hi folks,

So, I'm dealing with some suspension stuff right now. I'll try to provide as much detail as possible and I ask for your advice.

Lately, I have been noticing that my car is a lot more bouncy than it used to be. I've also noticed that it 'shudders' a lot more when I go over pretty decent bumps in the road like on highways and such or cobble stone areas of the city. I guess you'd call this 'after shock' of the bump or whatever. Also, depending on how big of a bump or groove in the road I hit, sometimes the car will jerk the wheel on my pretty significantly.

I'm taking it to Sears on Friday morning to get their 'free suspension inspection' that they do hoping they find something.

Something is definitely up with the car. I'm hoping to get it fixed under warranty (before that expires in another 1,000 miles) so that I can finally drop the car on the Espelirs I have sitting under my desk at work, but if I need to buy struts, etc. I might as well sell the Espelirs and get coilovers as it'll be the same price and much easier install, albeit likely a little more yearly maintenance.

Any opinions?

[DeanM45]

Your symptoms are pretty indicative of bad strut(s). The strut is there to keep spring in "check" during compression or extension.

[Ilya]

I'm about to hit 88k...

[szh]

I'm about to hit 88k...

At that mileage, they are probably just worn out and need to be replaced ...

Z

[06M4.5]

sounds like your riding on springs, you should also replace all 4 sway-bar links.

I did my links at 59k mls.

[Ilya]

Thanks Freddie and others...the more responses and suggestions I get the better. I really hope Sears finds a bunch of stuff.

[merlinq2]

I have had the same issue, lowered the car, and then developed the After Shock. Took it to the dealer had it aligned and the issue was dramatically reduced. It is still there.
I think the M35x does not like to be lowered, the initial spring; strut shock set up was designed for settling down the car based on the extra weight associated with the awd.
I did not have any of these problems prior to the drop; the car was smoother, handled way better and was nicer to drive. Now with the stiffer springs, I spend more time trying to avoid bumps etc.
-Going back to the stock set up.
I have three different shops look at the struts and all give them the thumbs up. They tell me to wait until I get the bouncy front end before I spend the money.
I agree that a certain mileage the struts will go, they are engineered to break down over time. In my case the springs did more harm to the car than good. The looks were improved tenfold; however, the ride was compromised.
After some research into asphalt and heat I found that the oppressive heat we are having in Southern Ontario is wreaking havoc on the roads, they are breaking down and more and more road surfaces are rough bumpy; pot holes are soon to follow.
By the way, taking a tech around with you is useless; a lot of them don't drive the M's so to them they have no idea what to look out for.
My wife can drive my car and not report anything, I drive it I hear, see and feel everything! Why would a tech be any different?
Let us know what you end up doing, once I revert back to my stock set up I will let you know what I found
Not sure why you would need to replace the sway bar links; the sway bar bushings I can see the links – not so much.

[Ilya]

Thanks Merlin...however, I'm still on the stock suspension. I'm trying to avoid installing the springs unless I know I won't have to replace the struts in 10k miles. I don't want to do the same install twice.

[merlinq2]

IMO keep it all stock- i think the engineers that designed all of the bits that assemble to make an infinti know better than we do. Alignment first, struts and bushings second. Springs never go unless the snap or break.

Try the alignment, that took care of about 60 % of my issues- the rest is a result of the springs.

Good luck

[Ilya]

Just finished with Sears...both rear shocks have like no resistance when they lifted the car and pushed up on the wheel. Infiniti will bereplacing,I haveno doubt.

They said the front is perfectly fine. So once the backs get replaced, I'll finally be getting lowered.

[wingFeather]

I'm glad you were able to learn what the cause was. FYI - shocks are "wear items" (such as oil, air filter, tires) and not covered by factory warranty. I would get an estimate from Sears to compare with what the dealer will charge you.

[merlinq2]

Just finished with Sears...both rear shocks have like no resistance when they lifted the car and pushed up on the wheel. Infiniti will bereplacing,I haveno doubt.

They said the front is perfectly fine. So once the backs get replaced, I'll finally be getting lowered.

Really interesting how the rear shocks were transmitting issues into the front end. That shuttering over bumps was coming from the front end right?

Rear shocks are very easy to do! The fronts are better left to the Pro's.

Good luck and let us know if the replacements solve your issues

[06M4.5]

I would change all 4, don't fool yourself and think that at 65k mls your shocks or struts are still good on a +4k lbs car. save your money and do it once instead of twice.

I have seen them go bad as early as 50k mls, because the springs are so strong most will think that struts/shocks are even good at 100k mls

this is what's called driving on springs

[Ilya]

I might go out and setup my GoPro camera on each fender and record each wheel as it goes over a rough road to see how the suspension is acting. From what I've been told...it should be pretty smooth...if the wheel is going up and down a lot (looks like it's rattling - I'm sure we've all seen the car in front of us that seems like it's about to lose a wheel) that means that strut/shock is on it's way out.

[Ilya]

Here is a video I created to show the suspension.

Can any of you tell anything from this video?

http://www.youtube.com/watch?v=WnIr8RQT-Mg&hd=1

[DeanM45]

It would be a little bit easier if you swapped the right panels (you have the front on the bottom on the right and the front on top on the left).
Can't really tell anything abnormal from the video but the M is such a heavy but fairly stiff car that it'd be hard to tell visually at speed.

By any chance did you do the"bounce test"? get a corner moving up and down (be careful where you push, the sheet metal is not that thick). Then stand back and the corner should come to rest within 1/2 a cycle (should bounce partially up or down and then stop). That is the VERY generic way of checking struts. The stock setup is very stiff comparatively speaking against other cars so if it is "easy" to push down then the strut is probably bad.

[Ilya]

It would be a little bit easier if you swapped the right panels (you have the front on the bottom on the right and the front on top on the left).
Can't really tell anything abnormal from the video but the M is such a heavy but fairly stiff car that it'd be hard to tell visually at speed.

By any chance did you do the"bounce test"? get a corner moving up and down (be careful where you push, the sheet metal is not that thick). Then stand back and the corner should come to rest within 1/2 a cycle (should bounce partially up or down and then stop). That is the VERY generic way of checking struts. The stock setup is very stiff comparatively speaking against other cars so if it is "easy" to push down then the strut is probably bad.

I did that because my video recording was of poor execution lol.

Basically, top two panels are trip going north on that road. Bottom two are going south on that road.

And I did not, I shall do this tomorrow. I shall also, per another persons suggestion, get in the trunk and try to do similar tests.

[06M4.5]

most of the time that won't work as the M's springs are to stiff.

[07sportm35]

I am surprised the dealer is giving you the runaround. If you have a factory warranty, it is in their best interest to do as much work on your car as possible because the dealership gets paid.

Also, before your warranty runs out, get as much work done on your car as possible. Usually there is a case for the front steering rack and the rear differential to be replaced. Try another dealer if you can. Best of luck.

[Ilya]

I'm going to email the service manager himself and see what he says. I will also link him to that video and tell him what Sears told me.

Also going to buy a thermometer gun which I have been told will help me diagnose. Lets say all the shocks/struts are 60* when the car has sat all night. After I drive, they should be say 120*. If they are still 60* or close, that means there is a leak in the strut/shock, etc.

http://shop.advanceautoparts.com/webapp ... ometer+gun

[Ilya]

Update:

Went to the dealership again and this time, after some prodding, they sent their best tech on a ride along with me driving. We went all over the place, and the tech said he had to check the bushings because it seemed like a bushing problem.

Long story short, I'm getting a new steering rack. There are a couple of bushing on it that are a part of the rack and not replaceable and they are shot (metal on metal, lots of movement, etc.)

Springs/Struts are probably fine or just worn and won't be getting replaced I don't think. So, I may be selling my Espelirs and going with BC coilovers. Haven't decided yet.

[merlinq2]

wow after all that it wound up being a steering assembly? that is truly odd. not a common problem.

[Ilya]

Yeah, never heard of this either and I've been on the forums for a couple years now. But, if it gets fixed, it gets fixed.