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      05-16-2015, 03:23 PM   #1
Twixboy
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Rear spring broken

I just found out one of my rear springs is broken. The shop said I can drive on it for a while if I want. They are quoting 1 hour of labor to replace the spring, or 4 hours if I want to replace all 4. No extra labor if I want to buy shocks to replace too. What would you do in my situation? Does 4 hours @ $100/hr reasonable?
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      05-16-2015, 04:15 PM   #2
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4 hours for all 4 springs sound extremely fair to me. For the fronts that entails pulling the suspension all the way off the car, so its quite a bit of work. I haven't done a suspension swap on this car yet, but in the past I've found around 6 hours is a reasonable estimate.

That said, there is really no need to replace the front springs in this case. The rear springs are widely known to fail, but the fronts are not. You should definitely replace the rear spring, and I would say do both springs at the same time, as the new one will behave slightly differently than the old one and could show up as unpredictable handling if you have both and old and a new spring on the car at the same time.

Whether or not it makes sense to replace the shocks at the same time is mostly dependent on mileage. People here frequently replace the stock suspension between 80k-100k miles, but I think there are also plenty of people who have gone longer than that.
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      05-16-2015, 04:45 PM   #3
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I agree, just do the rears.
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      05-16-2015, 07:25 PM   #4
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Stock shocks are starting to wear by 40k miles or so.. I'd change 'em all if they are original and your mileage is anywhere north of that.
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      05-16-2015, 09:34 PM   #5
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how many miles on the cat Twix? of course, if your looking for an excuse to upgrade your suspension…
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      05-16-2015, 09:49 PM   #6
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Quote:
Originally Posted by Vanne View Post
how many miles on the cat Twix? of course, if your looking for an excuse to upgrade your suspension…
lol, you read my mind. I have 58k on the clock. I know springs will basically last forever except the bad batch of rear OEM springs, but if I replace the 2 rear springs with OEMs at a cost of nearly $300 for parts I might as well just buy a set of H&R sports or Eibach Pros. And if I'm doing springs, I might as well do the shocks too so I don't have to pay for labor twice right? The Koni yellows might be more performance than I need. Are there any cheaper options that still perform better than stock and can handle a slight drop? How are the Bilstein B8 series?

For the price of springs/shocks, I noticed I can get some budget coilovers for about the same price or a couple hundred more. H&R Street Performance for $1200 seems to be the beginning benchmark on the forums, with everything else being more expensive. But I also found other brands for much less. I'm not looking to track my car, maybe just autocross once in a while for fun. Any opinions on these coilovers:
BC Racing $1000
ST X Performance $977
Megan Racing EZ Street $799 - Popular brand for the S2000
FK Silverline $695 - I've read these use Koni inserts. Why so cheap?
FK Highsport $543

Last edited by Twixboy; 05-16-2015 at 10:11 PM..
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      05-16-2015, 10:38 PM   #7
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lol Twix, yeah, some of those sound very cheap, sadly from what I've learned over the years with shocks n springs its pretty much " you get what you pay for" ..

suspension is one of those personal things that some others might not choose what you like. but anyways, my thinking is this, i didn't want to chuck any coil over system in there downwards of the KW series, and since i don't track that much, id stay with the current setup, but then get the best setup you can for the cash your willing to spend.

for me that was Bilstein HD's with H&R sport springs (proven set combo our our platform), and i can tell you, its pretty darn good, and probably would not want anything much harsher or the car. Here in DXB the roads are pretty darn fine.

as i said, its a personal choose, only thing i can tell you, is if changing anything, go for quality stuff, you will thank yourself for it later.
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      05-17-2015, 08:24 PM   #8
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Quote:
Originally Posted by Vanne View Post
lol Twix, yeah, some of those sound very cheap, sadly from what I've learned over the years with shocks n springs its pretty much " you get what you pay for" ..

suspension is one of those personal things that some others might not choose what you like. but anyways, my thinking is this, i didn't want to chuck any coil over system in there downwards of the KW series, and since i don't track that much, id stay with the current setup, but then get the best setup you can for the cash your willing to spend.

for me that was Bilstein HD's with H&R sport springs (proven set combo our our platform), and i can tell you, its pretty darn good, and probably would not want anything much harsher or the car. Here in DXB the roads are pretty darn fine.

as i said, its a personal choose, only thing i can tell you, is if changing anything, go for quality stuff, you will thank yourself for it later.
Is Bilstein HD the B6 or B8? From Bilstein's website:
"The BILSTEIN B6 Sport is a mono-tube gas pressure shock absorber designed to dampen wide-ranging vibrations very precisely. Where an oil shock absorber produces an oily foam and creates a spongy driving feeling after a very short distance, the BILSTEIN B6 Sport remains constant, precise and stable. The BILSTEIN B8 Sprint is a mono-tube gas pressure shock absorber specifically designed to be used with lowered vehicles with shorter stroke. It also offers the same advantages as the BILSTEIN B6 Sport shock absorber."

Seems like they recommend the B8 for use with lowering springs.
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      05-18-2015, 01:21 AM   #9
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twix mate, not telling you to buy these mate, gotta do your own research man.. i bought these,http://www.turnermotorsport.com/p-15...-4-shocks.aspx
and am very, very happy with them, add some H&R springs and your looking around a grand… plus install if you don't do it yourself..

have a good look at what your requirements are mate, and then add things up.. Shippy helped me out with choosing mine and he has some really good info on this set..

I think if i did more than a few track days a year, i def would opt for the KW series.. ymmv of course
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      05-19-2015, 11:41 AM   #10
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those are a really reasonable price. maybe something for later this year.
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      05-19-2015, 10:57 PM   #11
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These aren't a "bad" batch of OEM springs. These are prone to breaking especially in areas with salt as the paint on the springs tend to crack and the elements wear away at the metal. Every picture I've seen, including mine, are all broken in the same exact place- about a quarter coil on the bottom half of the spring.

If you're replacing your rear springs, you don't have to replace the fronts. You shouldn't also feel obligated to switch out shocks along with the rears because they can be very separate jobs compared to the McPherson-styled fronts.

Knowing that the OEM style springs are determined to break, I highly recommend switching to a different manufacture. My car has been riding on broken springs for the two years I've owned it before I bought an ST lowering spring kit off of Amazon. It was a perfect match as the rear drop remained virtually the same when compared to the "chopped" springs. The front remained about the same as my stock Sport Suspension.

With that being said, I do recommend a suspension refresh if the car asks for it. Entry-level coilovers DO NOT mean that it will perform better than lowering springs and shock/struts. By about 100k, I decided to do a suspension refresh. The front springs were shedding a little paint, but that's about it. If you haven't swapped the strut mounts, chances are they're cracked too as were mine. Lastly, the shocks weren't even completely blown as they all had just a little bit of rebound when compressed- a pretty big surprise to me.
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      06-01-2015, 02:54 PM   #12
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Quote:
Originally Posted by Twixboy
I just found out one of my rear springs is broken. The shop said I can drive on it for a while if I want. They are quoting 1 hour of labor to replace the spring, or 4 hours if I want to replace all 4. No extra labor if I want to buy shocks to replace too. What would you do in my situation? Does 4 hours @ $100/hr reasonable?
Check YouTube for "BMW Z4 Spring Repair." The video shows what's involved and the time it takes to complete. I didn't think it was too complex, but the repair shop is probably costing an hour for each replacement, not for the combined time that's actually involved.
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      06-01-2015, 04:18 PM   #13
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I performed this fix several years ago, it wasn't that bad. In fact I didn't even use a spring compressor as it was much easier to use the carjack on the control arm to compress the spring when bolting it back into place.

Like Juggernaught said, find an online tutorial. I think I used one from the forums that was merely pictures & text.

Ended up just getting two new stock springs from Tischer to keep costs down. Pic of my busted spring on the left:

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      06-01-2015, 04:24 PM   #14
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bite the bullet and get coilovers. i wouldn't even bother with springs. i absolutely love my H&R coils.
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      06-01-2015, 07:17 PM   #15
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I replaced my rear spring pads when I did the shocks about a year ago.
That part of the job was fairly easy.
I think the hardest part was disconnecting/reconnecting the headlight level sensor linkage.
(Remember to disconnect/reconnect the headlight level sensor linkage.)
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      06-01-2015, 07:56 PM   #16
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Quote:
Originally Posted by dubsesd View Post
bite the bullet and get coilovers. i wouldn't even bother with springs. i absolutely love my H&R coils.
Ah, my thread got revived. I had forgotten about this when school started up again (please shoot me now. i'm a dad of 2, work full time w/a 3 hr total commute, and also getting my MBA at night). So it's about $1200 for H&R coilovers vs $850 for H&R sport springs with Koni yellows. If I leave the coilovers at the same drop height as the H&R sport springs, what's the difference in handling feel like? Besides adjustability, what other advantages do coilovers give the car?

Also, how long does it take to adjust the coilovers up and down? It's just a matter of putting the car on jack stands and turning a key right? Maybe 1 hour tops for all 4 corners including getting out the tools and putting them away?
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      06-02-2015, 11:40 AM   #17
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Quote:
Originally Posted by StickMon View Post
I replaced my rear spring pads when I did the shocks about a year ago.
That part of the job was fairly easy.
I think the hardest part was disconnecting/reconnecting the headlight level sensor linkage.
(Remember to disconnect/reconnect the headlight level sensor linkage.)
A. Why do you need to disconnect it (is it mechanically in the way)?
B. Where is it?

Thx.

About two weeks ago my daughter said to me that from the rear view while in the garage one side of my car seemed slightly lower than the other. I took a look and she was right, but then I moved on to something else. I'll have to check that spring. How is it possible that BMW/supplier can't get a coil spring right? 50 yr old pick up truck springs don't fail after being abused.

Also, does anyone have OEM rear springs (non-broken) that they would be willing to sell?

Last edited by elerner61; 06-02-2015 at 12:03 PM..
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      06-02-2015, 12:36 PM   #18
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It's on the right rear lower control arm about 1/2 way between the diff and the wheel.
A little box with a lever sticking out connected to some small linkage.
To remove the rear spring you have to disconnect the shock and then put your foot on the brake caliper and push the suspension down.
It's debatable that the level sensor has enough travel to allow it to extend that far.
Disconnecting the linkage is a bit fiddly, but it beats breaking it.
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      06-02-2015, 12:54 PM   #19
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Quote:
Originally Posted by StickMon View Post
It's on the right rear lower control arm about 1/2 way between the diff and the wheel.
A little box with a lever sticking out connected to some small linkage.
To remove the rear spring you have to disconnect the shock and then put your foot on the brake caliper and push the suspension down.
It's debatable that the level sensor has enough travel to allow it to extend that far.
Disconnecting the linkage is a bit fiddly, but it beats breaking it.
Ahh, I see! (said the blind man). Thanks!
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