1998 Q45 Strange Suspension Problem

[ymh]

Hi,

I was hoping someone could help me with a suspension problem I'm having with my 1998 Q45. The car has 128,000 miles on the odometer and it is the standard model, regular suspension, not Touring. The front and rear struts were changed by Infiniti in January of this year.

Here's the problem: When going over freeway expansion joints, the car seems to have a very odd bounce in the ride. I hope I'm using the right terminology, but the car seems to sway from either Front Left to Rear Right or Front Right to Rear Left. Meaning the car doesn't seem to go up and down evenly on all four corners. Hope that makes sense. It feels like your riding in boat and are being tossed around by the waves. It's not that dramatic, but it doesn't feel normal. I don't remember the car doing this when I first got it 5 years ago with 80,000 miles on the odometer.

I've taken the car back to the dealer a couple of times and they say everything checks out fine.

Any ideas on what specifically I could check?

Thanks in Advance.

[BadQ45t]

Have you serviced the tension rods? those go bad for sure, if your at 130k and have never replaced them for sure those are worn out.

Did you do springs and shocks at the same time. Springs usually lost longer but I always change springs when i do shocks.

[Q45tech]

Could just be that since you bought car at 80k, you were only use to worn out shocks!

Drive a brand new M45 [weight equivalence] over the same roads as a reference.

Shocks are just a tiny factor in rebuilding a worn/worn out suspension. Everything rubber has changed in hardness/softness.

Another factor to examine is the condition of the 4 old in inventory shocks.The old of having a single leaker [of nitrogen gas] after 10 years are obviously higher.

Unused shocks can be tested before installation by measuring the time [few seconds] it takes for self expansion from fully compressed state.

[maxnix]

Did they replace the front strut bearings and confirm the front spring mounts were still good? How about all anti sway bar links? Tension rods?

So much you are not telling us. Did they not tell you either?

[rover3l]

I am afraid I am going to repeat what most everyone else is advising. I recently did my suspension and it involved struts, all rubber, mounts, sway bar bushings, tension rod bushings.

Do you have any knocking sounds over bumps or any other unusual noises from the suspension?

How are the tie rod ends? also replaced mine as there was some wear.

[ymh]

Hi All,

Thanks for your replies. The tension rods, front right and front left, were replaced in the middle of 2007 when the car had approx. 112k miles on the odometer.

The springs were not replaced when the struts were replaced.

Unfortunately, I didn't get a detailed breakdown of what the dealer replaced when I got the struts replaced.

I initially took the car in, because the car was making a clunking sound from the front left corner when I went over something like a speed hump even at normal speed (less than 20mph). The front struts (and rear struts) replacement fixed that.

I don't hear any strange noises coming from the suspension now. And the car seemingly rides fine at speeds below 40mph, or city driving. No odd jouncing or bouncing. Sharp bumps / potholes don't cause the problem either. But once I get on the freeway (at higher speeds, 60mph +) and there is an expansion joint or dip in the roadway, you can then notice the strange oscillation right after you pass the dip.

Perhaps it is a defective shock or spring or other rubber bushing component that has been overlooked.

I need to get the service advisor or technician to come on a test drive with me to show them the problem.

I appreciate the direction and advice from you all.

Thanks for taking the time.

[maxnix]

[QUOTE=ymh]Unfortunately, I didn't get a detailed breakdown of what the dealer replaced when I got the struts replaced.

I initially took the car in, because the car was making a clunking sound from the front left corner when I went over something like a speed hump even at normal speed (less than 20mph). The front struts (and rear struts) replacement fixed that.

Perhaps it is a defective shock or spring or other rubber bushing component that has been overlooked.

QUOTE]Springs should be fine. Did they check the steering rack bushings? If not, take it somewhere else!

You have to have a copy of the RO (Work Order) detailing the service since that's the law.

Get the service adviser to print out the Infiniti Dealer performed service history for you. All of it since day 1.

[rover3l]

What tires and pressures are you running?

[ymh]

Not sure if they checked the steering rack bushings.

All the 4 struts weren't done at the same time but they were done in pairs (front) and (rear). The fronts were done in Sept. 08 and the rears were done in Jan. 09. This was due to a timing issue on my side and a parts availability issue on the dealer's side. Was also out of the country for a month and half between those dates.

The work orders for the strut replacements states:

September 2008

CUST STATES VEHICLE BOTTOMS OUT OVER BUMPS WHEN LOADED WITH PASS. CHECK AND ADVISE

REPLACED FRONT STRUTS MISC DR. TRAIN/AXLE/STEER-MISCDParts ABSORBER KIT-SHOCK C-56105-6P925 ASR Qty 2

January 2009

REPLACED REAR STRUTS MISC DR. TRAIN/AXLE/STEER-MISCDParts ABSO SHCK RE-56210-6P027 ASR Qty 2

[ymh]

The tires were changed by Infiniti on May 2007. They are Michelin Energy MXV4 P215 60R16. All are running 34psi and seem to be in very good condition.

[BadQ45t]

I hate to say this but STOP going to the Infiniti dealership. This is way too old of a car to be going and paying high retail.

this guy is in Houston, anybody know a good shop in Houston he can go to.

in the meantime, you did all this work with them, put a service advisor in the car and make him go for a ride to see what your talking about.