Suspension replacement question

Hi, my car is 2004 330i, 120k km. When going over low speed humps, it bounces and produces squeezing noise, the sound like rusted spring. Other than that it rides fine, but never comfortable. Does it look like my suspension is on the way to go?

The car is 95% daily and road condition is not so good, so comfort is priority. Also I think my car is already low enough and often risk curbing the bumper in parking lot, so I don't want it to be lowered.

I have a few questions that hope to get some answers.

How do I know my stock suspension is sports or not? The realome with my VIN lists standard, sports, m-sports and poor road version, all in one page. So is there any other way to determine it?

I'm looking at Bilstein HD - it lasts longer but does it lower the car and make harsh ride?

Koni Yellow - Are they harsher than stock? Do they lower the car?

Sachs OEM - Does it last even shorter than the original? This is my biggest concern.

Thanks.

Originally Posted by TonyJ

Hi, my car is 2004 330i, 120k km. When going over low speed humps, it bounces and produces squeezing noise, the sound like rusted spring. Other than that it rides fine, but never comfortable. Does it look like my suspension is on the way to go?

The car is 95% daily and road condition is not so good, so comfort is priority. Also I think my car is already low enough and often risk curbing the bumper in parking lot, so I don't want it to be lowered.

I have a few questions that hope to get some answers.

How do I know my stock suspension is sports or not? The realome with my VIN lists standard, sports, m-sports and poor road version, all in one page. So is there any other way to determine it?

I'm looking at Bilstein HD - it lasts longer but does it lower the car and make harsh ride?

Koni Yellow - Are they harsher than stock? Do they lower the car?

Sachs OEM - Does it last even shorter than the original? This is my biggest concern.

Thanks.

Shouldn't be any bounce at all. If you have bounce your shocks need replacing. A 2004 vehicle shouldn't have any spring issues, unless its been battered. Just go with what the spec says for you vehicle. Don't buy cheap.

Any other suggestions? I guess the first I'd like to know is whether the stock suspension is sports or not?

Originally Posted by TonyJ

Any other suggestions? I guess the first I'd like to know is whether the stock suspension is sports or not?

Based on the limited information you have provided (330i 2004) it is difficult to say although I would suspect not sports as standard. See the following links.

http://www.realoem.com/bmw/partgrp.d...25&hg=31&fg=10

http://www.realoem.com/bmw/showparts...69&hg=33&fg=45

That's the page I went to with all the detailed selected. It just lists all suspension types.

I can peep into there and see the strut and springs. Is there any visual difference between them? Or the bumper height on a 17" wheel?

Anyway, will the Bilstein HD or the Koni fit either sports or non-sports type?

Originally Posted by TonyJ

That's the page I went to with all the detailed selected. It just lists all suspension types.

I can peep into there and see the strut and springs. Is there any visual difference between them? Or the bumper height on a 17" wheel?

Anyway, will the Bilstein HD or the Koni fit either sports or non-sports type?

There will be little visual difference between struts because they all have to fit into the same space attached to other components at the same points. The difference will be in their behaviour in responding to the forces acting upon them. Their damping properties. This is determined by their internal design properties. Springs too may look identical, for the same reasons, whilst exhibiting different spring properties. The properties of any spring are determined by the spring rate of the materials from which they are made. From what is available on the internet Bilstein do provide compatible shocks for your vehicle as do Koni.

Check for sport steering wheel and seats. If present, you likely have sports suspension as well unless a PO swapped them both in (unlikely). They are all part of the same package.

Originally Posted by rdogthenut

Check for sport steering wheel and seats. If present, you likely have sports suspension as well unless a PO swapped them both in (unlikely). They are all part of the same package.

What does the sport steering wheel and seat differ from the standard one? Flat bottom?

I'd just google that for pics if you don't know already.

Originally Posted by rdogthenut

I'd just google that for pics if you don't know already.

That's acutally more confusing. My wheel looks like this:
http://www.bmw-driver.net/forum/showthread.php?t=25820

But again all the E46 I've seen have a wheel like this. Some of the images are labled sports wheel but some don't.

Tony, that's a sports package wheel, and I'm 99% sure that you have the sports package. All 330 sedans came with a sport suspension effective mid-2001 model year, regardless of whether they had the sports package or not. At least that was the case with US cars, but taking into account that the rest of the world always gets better goodies than US, I'd say you have the sport package with almost 100% certainty.

Having said that, I don't know why you would want to go ahead with anything else than Koni yellows. They are adjustable, and at their softest setting they will be just like your stock suspension if not any softer (after a settle-in period of course).

I'd pass on the Billy HD's, they have a harsh ride and you're stuck with them once you put them on because they are not adjustable. OEM is Sachs, and they don't have the same longevity you'd expect from either the Konis or Bilsteins.

edit: Also, struts and shocks don't lower the car. It's the springs that does that. Just mate your stock springs with Koni yellows, and you'd have a sweet ride.

Originally Posted by SeanC

Tony, that's a sports package wheel, and I'm 99% sure that you have the sports package. All 330 sedans came with a sport suspension effective mid-2001 model year. At least that was the case with US cars, but taking into account that the rest of the world always gets better goodies than US, I'd say you have the sport package with almost 100% certainty.

Having said that, I don't know why you would want to go ahead with anything else than Koni yellows. They are adjustable, and at their softest setting they will be just like your stock suspension if not any softer (after a settle-in period of course).

I'd pass on the Billy HD's, they have a harsh ride and you're stuck with them once you put them on because they are not adjustable. OEM is Sachs, and they don't have the same longevity you'd expect from either the Konis or Bilsteins.

Thanks Sean. So that's one question addressed.

I was mainly concerned whether the non-OE strut such as the Koni will lower the car, which I don't want any lower. Is it compatible with original springs?

Originally Posted by TonyJ

Thanks Sean. So that's one question addressed.

I was mainly concerned whether the non-OE strut such as the Koni will lower the car, which I don't want any lower. Is it compatible with original springs?

Yes, see my edit above

Originally Posted by SeanC

taking into account that the rest of the world always gets better goodies than US

haha. You know what we talk about AU cars? The rest of the worlds always gets cheaper cars!