Bilstein B4 kit
- Thread starter Dr. Zed
- Start date
Attleborough, Norfolk
Haha, BMW definitely was quirky with their PN's. Though it always amazes me how similar this car is to the e46Dr. Zed said:
While you have the front struts apart you'd be daft not to swap the springs. Rear ones are easy to do with hardly any tools but the fronts are scary! No doubt someone will be along to say the opposite though 
I agree. Exactly what I was saying earlier about the rears. If the car is a keeper and you're not on a really tight budget then do the front springs while its all apart.Rockhopper said:While you have the front struts apart you'd be daft not to swap the springs. Rear ones are easy to do with hardly any tools but the fronts are scary! No doubt someone will be along to say the opposite though
Don't find the fronts scary tbh, but then I've had plenty of practice now.
Rockhopper said:While you have the front struts apart you'd be daft not to swap the springs. Rear ones are easy to do with hardly any tools but the fronts are scary! No doubt someone will be along to say the opposite though
The issue is trying to find front springs in any sort of decent time frame..
enuff_zed said:I agree. Exactly what I was saying earlier about the rears. If the car is a keeper and you're not on a really tight budget then do the front springs while its all apart.Rockhopper said:While you have the front struts apart you'd be daft not to swap the springs. Rear ones are easy to do with hardly any tools but the fronts are scary! No doubt someone will be along to say the opposite though
Don't find the fronts scary tbh, but then I've had plenty of practice now.
I've been looking for springs but no luck in the UK really.
I didn't find the fronts to bad either to be honest.
you are probably fine with re-using them, mine looked ok if you go back further in the pics, the rears are what seem to have the common issues. Do you have RockAuto.com in the UK? They have front springs available from Lesjofors. They are Part Number 4008510. They are only $36. Maybe search that number up and see if it pops up on any UK parts providers.
https://web.tecalliance.net/lesjofors/en/parts/cars/assigned?assemblyGroupId=100113&targetId=16828&typeNumber=16828&targetCountry=AT&page=0#@brc/brands:Car;targetType:cars/assem:BMW%2520Z4%2520Roadster%2520(E85)%25203.0%2520i;targetType:cars;targetId:16828;typeNumber:16828;targetCountry:AT/lnkparts:Coil%2520Springs;targetType:cars;assemblyGroupId:100113;targetId:16828;typeNumber:16828;targetCountry:AT;page:0
enuff_zed said:
It's well known the oem/sachs only last around 30K. Bilstein's will last 60K+ easy.
Have a search on the forums to confirm the above but Bilstein's are built to a much higher standard. In fact to confirm what others have said on the forum my mechanic just called as he's coming to do the EGR on Friday and he said himself Bilsteins are a quality shock as I'm just about to plac emy order and sent him a screenshot to double check everything before I do. 37% off today on autodoc and I have a visa card which gives me 5% cashback on the total amount too.
Late to this epic wanted thread but I find myself in a similar situation. I’ve got shocks (sach) and will be reusing the old rubber dust shield. I’m pairing it with my m sport springs… question is what bump stops or dust shield kit do I need to buy? Or will any be compatible?
SonnyA85 said:
Oh my days, is this coming from the same ‘fact based’ knowledge pool that electric car owners don’t have range anxiety?
Where is the fact based evidence that Bilstein shocks last twice as long a Sachs shocks? 30k vs 60k
What you have is a situation where a lot of owners have replaced 10yr old+ Sachs shocks with bilstein’s in the belief they will be better, or because at the time they might have been cheaper than Sachs.
Do Bilstein offer a ‘’60,000 miles easy’’ guarantee?
If you have a look at Bilstein B8’s they’re developing a bit of a reputation for failure, and they’re an even more substantial build (different type of shock) to B4’s
O.P. You will be absolutely fine with Sachs shocks…. Most shocks will be dead after being run for 15 years even if they haven’t done really high mileage.
Yeah, sachs are a perfect set to buy if keeping the non-sport springs. I was about to buy them for my car before i discovered my rear coils were cracked. Ended up using that as an excuse to buy the M sport springs and comparable B6 Struts/Shocks. Luckily the Lesjofors coils were very inexpensive since all i could find was originial BMW equipment springs which cost tons of $$$$$ and the H and R springs were way too low for my liking.
Some quotes from this forum
Several folk at least 5-6 have had the OEM shocks absolutely knackered at 40-60K.
"The biggest problem with the Oem sachs shocks is that usually when they're knackered you won't see it till they're off the car. Its only then when separated from the springs that you can actually see how inoperational they are. Folks on here and other forums have had them be knackered on a whole range of Bmws at less mileage than your car is and certainly many years younger. The sach shocks used on Bmws of this vintage are pretty notorious for being crap both in the trade and on the net. Ive seen them literally fall apart when taken off on an 80k car.
Bilstein have a reputation for quality, hence why folks on here (including myself) have opted for them over using the sachs again. Apparently the supply problems are being caused by Oem demand for their shocks putting the aftermarket on the back burner.
As an alternative I did consider koni. They're usually pretty good but I have read recently on some Bmw forums that there have been some issues with reliability.
I've paired tge b4 with eibach springs. Not for the additional 10mm or so of lowering but because their initial spring rate is softer than the Oem M Sport ones, making them a bit more compliant over smaller bumps/ruts in the road."
https://z4-forum.com/forum/viewtopic.php?t=105766
"I've seen them knackered at 45,000 on an e46 cab. Initially i was just changing a broken spring but once i took the strut off i realised the shock was kaput. Did the front pair and a few weeks later did the rears. All 4 were screwed to difffering degrees and the car was much better for the new shocks. I've also seen them fall apart on the rear of another e46 cab at 80k. On that one one was leaking but I still didn't expect the thing to separate into two parts when I removed the shock bottom bolt. It literally hit the floor with the car on the ramp.
I understand the disbelief though. You wouldn't/shouldn't expect that on a modern cars, especially premium brands and i totally understand why you woukdnt want to spend serious money on replacing parts on a car you cant tell are screwed. But all i can say based on what ive personally experienced, heard/seen from friends in the trade and seen/read on the net about sach stuff on bmws of this vintage is why I switched to bilstein. mine came in at circa £300 which I seem to remember is what euro/gsf/andrew page etc all wanted for sachs on and that was trade as well."
I can't find the post now because i looked through about 30+ threads but one guy switched his out after 40K miles for B4's as they were knackered. He drove the car 30K miles before selling it to a mate who then also drove it for 30K miles before selling it on and they were still okay. So he reckons B4's do around 100K miles and that is normal for a shock absorber. OEM however are crap and the numerous reports of them on here failing after 40-60K but they have no idea how long they have been knackered for because the only way to know is to take them off the car so they could have been knackered for years.
Also SACHS Advantage is no longer made and that is the OEM replacement for M Sport suspension. The SACHS you are all buying is for standard suspension.
B4 is also for standard suspension you should be buying the B8 but lots go for B4 for more comfort the B8 is stiffer.
Several folk at least 5-6 have had the OEM shocks absolutely knackered at 40-60K.
"The biggest problem with the Oem sachs shocks is that usually when they're knackered you won't see it till they're off the car. Its only then when separated from the springs that you can actually see how inoperational they are. Folks on here and other forums have had them be knackered on a whole range of Bmws at less mileage than your car is and certainly many years younger. The sach shocks used on Bmws of this vintage are pretty notorious for being crap both in the trade and on the net. Ive seen them literally fall apart when taken off on an 80k car.
Bilstein have a reputation for quality, hence why folks on here (including myself) have opted for them over using the sachs again. Apparently the supply problems are being caused by Oem demand for their shocks putting the aftermarket on the back burner.
As an alternative I did consider koni. They're usually pretty good but I have read recently on some Bmw forums that there have been some issues with reliability.
I've paired tge b4 with eibach springs. Not for the additional 10mm or so of lowering but because their initial spring rate is softer than the Oem M Sport ones, making them a bit more compliant over smaller bumps/ruts in the road."
https://z4-forum.com/forum/viewtopic.php?t=105766
"I've seen them knackered at 45,000 on an e46 cab. Initially i was just changing a broken spring but once i took the strut off i realised the shock was kaput. Did the front pair and a few weeks later did the rears. All 4 were screwed to difffering degrees and the car was much better for the new shocks. I've also seen them fall apart on the rear of another e46 cab at 80k. On that one one was leaking but I still didn't expect the thing to separate into two parts when I removed the shock bottom bolt. It literally hit the floor with the car on the ramp.
I understand the disbelief though. You wouldn't/shouldn't expect that on a modern cars, especially premium brands and i totally understand why you woukdnt want to spend serious money on replacing parts on a car you cant tell are screwed. But all i can say based on what ive personally experienced, heard/seen from friends in the trade and seen/read on the net about sach stuff on bmws of this vintage is why I switched to bilstein. mine came in at circa £300 which I seem to remember is what euro/gsf/andrew page etc all wanted for sachs on and that was trade as well."
I can't find the post now because i looked through about 30+ threads but one guy switched his out after 40K miles for B4's as they were knackered. He drove the car 30K miles before selling it to a mate who then also drove it for 30K miles before selling it on and they were still okay. So he reckons B4's do around 100K miles and that is normal for a shock absorber. OEM however are crap and the numerous reports of them on here failing after 40-60K but they have no idea how long they have been knackered for because the only way to know is to take them off the car so they could have been knackered for years.
Also SACHS Advantage is no longer made and that is the OEM replacement for M Sport suspension. The SACHS you are all buying is for standard suspension.
B4 is also for standard suspension you should be buying the B8 but lots go for B4 for more comfort the B8 is stiffer.
