Need Advice on Suspension Upgrade

[Tony0000]

Hi. New to this forum.

I recently bought a used 2009 128i. It's great. My only complaint is that the rear end frequently bottoms out. Potholes, bumps, changes in road gradient, you name it. (FWIW, I live in Michigan which has the lowest per capita expenditures on road. They're awful.) My mechanic (a BMW specialist) says there's nothing wrong with my car--it's just how it's built. So I'd like suggestions on cost-effective upgrades to the rear suspension to minimize the bottoming out I'm getting.

Many thanks,

Tony

[Gangplank]

What exactly makes you think it's bottoming out? With the runflats I found the ride to be jarring.

[SayHack]

The shocks might be shot.....im surprised your mechanic didn't catch that.....I have an 08 128i , Im redoing the whole suspension for this exact reason. (But im instilling coilovers with ///M control arm kit)

but factory shocks shouldn't be that expansion to swap (sachs original shocks + struts are around 350 for the set)

[Tony0000]

Gangplank: I don't have run flats. I think it's bottoming out because I do feel some travel in the rear end and I hear a scraping, which I assume to be the tires rubbing on the wheel wells.

SayHack: I'll have my mechanic check the shocks again. (I have almost 130k on the car.) Thanks for the suggestion about the M control arm kit and the Sachs shocks and struts.

Tony

[tracer bullet]

Stock wheels? What tire sizes? Maybe there is an offset problem and you are rubbing components earlier in the suspension travel than normal.

[asbrr]

Originally Posted by Tony0000

Gangplank: I don't have run flats. I think it's bottoming out because I do feel some travel in the rear end and I hear a scraping, which I assume to be the tires rubbing on the wheel wells.

SayHack: I'll have my mechanic check the shocks again. (I have almost 130k on the car.) Thanks for the suggestion about the M control arm kit and the Sachs shocks and struts.

Tony

At 130K - if these are the original shocks I wouldn't be suprised at all if they have worn out. They usually would look for visible signs of a leak, but who knows how long ago they may have leaked out. Can you bounce the rear end of the car manually / by hand? Does it oscillate more than once?

[Olgeezer1]

As long as you haven't broken a spring, a set of Bilstein B6's or Koni Yellows should work great on a stock suspension. Your stock shocks may just worn out and since the 1 Series was built to a price they weren't all that great to start with.

[02Pilot]

At 130k miles, I will tell you definitively that your dampers are worn out. And probably most of your suspension bushings. Maybe your springs too. At the very least, replace all the dampers. If you want to deal with it fully, do the whole thing at once and save yourself some labor.

[Tony0000]

Thanks to all for your input. It looks like I'm going to have to have the suspension re-checked. (I had it checked 1.5 years ago.) Then I'll start looking at Bilstein B6's and Koni Yellows.

Tony

[TURBO8]

I just installed some Bilstein B8's on mine. The ride and handling is much better.

If you go with Bilsteins, you won't need bump stops or boots, they come with them.

[Dackelone]

OP have you seen this thread ?

128i the ultimate handling machine...
https://www.1addicts.com/forums/showthread.php?t=575027


I agree, that with 130K miles... your suspension is shot/worn out. But nothing a set of shocks and springs couldn't cure.

Dack