Basic Strut/Shock Question - Need Help.

[NYNATIVE007]

Disclaimer: I’m a tax accountant by profession so I’ll gladly exchange basic tax advice for basic car advice.

I'm a long time visitor, but I don't post much. OK, needless to say, I’m by no means an expert in cars. I’m just looking to get some help relative to the M. I’ve searched this forum for help but most of the topics deal w/ threads that I feel are more advanced (lowering the car, DIY suspension questions, etc.) I have a very basic issue – hopefully there are others that can find the solutions in this helpful as well.

I have a 2006 M35 Sport with about 76K miles. I purchased it in 2009 w/ 30K miles. I know I need to replace something in my suspension but I’m not sure what. Here are my symptoms:

- When the car is level, the rear of the car sits a bit lower than the front.

- When I make sharp turns (i.e. in a parking garage) the car “wobbles” from side to side.

- Riding over potholes/bumps is obviously more noticeable then it was a couple yrs ago.


Here are my questions:

1. What would I need to replace? I don’t know the difference between a strut and a shock and how they relate to the M. I basically want to sound like I know what I’m talking about when I take it to a mechanic. I don’t plan on doing it myself.

2. How much would replacing what I need to cost me? Again, moreso so I know I’m not getting ripped off.

3. Would it be best to bring/buy my own aftermarket parts or would I be OK having them install whatever they have in stock? If so, what is recommended?

Again, I thank anyone who is willing to help. I apologize in advance for the basic/general nature of the questions above but I know there is a wealth of car knowledge in this forum. I’ve been on the forum ever since I purchased my M so I’m very grateful for the advice I’ve already picked up. Thanks in advance!

[CPJ LB]

Welcome!!

you can start by getting a set of KYB shocks/struts (the dealer will charge a very high price for shocks/struts).

Shocks will go in the rear, Struts go in the front. -- this will eliminate the "bouncy" ride feel from worn/old shocks also the clunk sound from going over bumps/pot holes. As far as the wobble from side to side, you may have your mechanic check your suspension parts (outer and inner tie rods, sway bushings, alignment, etc).

You can get good deals online on the KYB's. I've done the suspension upgrade on my car awhile ago and the KYB's are still great....there's a lot of threads that describe guys going with KYB's...

new-kyb-struts-t550245.html

[atlM35]

http://www.ebay.com/itm/KYB-GR-2-EXCEL- ... a4&vxp=mtr

shouldn't cost more than $250 for install of a full set at a reputable garage.
less than $600 total to bring the dampening back to a good state.

[elwesso]

Just so everyone knows, the difference between a "shock absorber" and a "strut" is this: A strut has only one purpose, and that's to prevent the car from bouncing (basically an anti-spring)... This would more/less be the case when the shock and spring are separate assemblies. A strut is actually part of the suspension, and it's considered a strut basically when the spring is mounted on the shock absorber.

The springs are what provides the "ride". If you hit a bump and you had no dampers (shocks/struts), the springs will oscillate at their natural frequency. The dampers simply provide a certain amount of damping to the springs so your not bouncing all over the place.

So, as stated the rear suspension would use "shocks", and the front suspension would use "struts".

Onto your notes, the fact that the car sits lower in the rear than the front would indicate to me that perhaps the springs are sagging. The springs are what controls the ride height (as they are what supports the weight of the vehicle), so if there's a question of ride height the struts won't fix anything in that regard.

What you're describing sounds a bit more like worn out suspension links like bushings or ball joints, not the dampers.

[NYNATIVE007]

Thanks guys! Very useful information. It helps my basic understanding a lot.

I'm gathering that I may have other issues other than just replacing my shocks/struts. I may have to take it somewhere for someone to look at it before I decide what parts I need to buy. But, from your posts above, I atleast have some understanding of what the issue may be. Thanks again.

If anyone in the Dallas, TX area is reading this and can recommend a reliable mechanic for suspension work that would be appreciated.

[elwesso]

I would maybe take the car to the dealer for a diagnosis, and then it could be taken to a regular shop for someone to turn the wrenches. really the suspension on this car is pretty typical for any car made within the last 20 years so there's not any big surprises. Something like this should be fairly easy to diagnose. Basically all you can do is get the car up on a lift and see if anything looks obviously worn or loose..