E90Post
 


 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > Suspension | Brakes | Chassis > Changed to 18' 162s (from 16' stock) - I think my front struts need changing



Reply
 
Thread Tools Search this Thread
      04-25-2016, 04:30 PM   #1
WhiteBeard
Lieutenant
United_States
156
Rep
545
Posts

Drives: slowly
Join Date: Feb 2016
Location: Jacksonville

iTrader: (0)

Changed to 18' 162s (from 16' stock) - I think my front struts need changing

So I recently upgraded from stock 16' RFTs to 18' 162 style on Conti DWS all-season. Despite the lower profile tires ride quality increased, I guess RFTs were so stiff and bad in this regard.
However, I started to notice on some bad roads, from time to time, when I hit some pothole, my front struts would hit bump stops (sorry, not sure if they are called that) and my front takes the hit really hard. I checked front struts and couldn't find any leaks, they seem to work well otherwise. It's only at those deep potholes when they are not sufficient anymore. I guess 18' rims require a bit stronger shocks/struts. I was wondering if I can change just the front struts to some descent ones - BUT I want to keep same comfort as stock ones and I'm not willing to sacrifice ride comfort AND I'm not looking to lower/drop my ride. I just don't want to keep collecting hard shuttering hits with my front. What options do I have? Thank you

Last edited by WhiteBeard; 04-25-2016 at 04:39 PM..
Appreciate 0
      04-26-2016, 09:03 AM   #2
thakid22
Captain
United_States
292
Rep
600
Posts

Drives: 2021 Bmw M340i M-Sport w/ VDC
Join Date: May 2013
Location: Little Rock

iTrader: (0)

Quote:
Originally Posted by WhiteBeard View Post
So I recently upgraded from stock 16' RFTs to 18' 162 style on Conti DWS all-season. Despite the lower profile tires ride quality increased, I guess RFTs were so stiff and bad in this regard.
However, I started to notice on some bad roads, from time to time, when I hit some pothole, my front struts would hit bump stops (sorry, not sure if they are called that) and my front takes the hit really hard. I checked front struts and couldn't find any leaks, they seem to work well otherwise. It's only at those deep potholes when they are not sufficient anymore. I guess 18' rims require a bit stronger shocks/struts. I was wondering if I can change just the front struts to some descent ones - BUT I want to keep same comfort as stock ones and I'm not willing to sacrifice ride comfort AND I'm not looking to lower/drop my ride. I just don't want to keep collecting hard shuttering hits with my front. What options do I have? Thank you
Your shocks may very well be worn. How many miles do you have?
But here is something I've found with the DWS on my 535i Sport...
They are very soft, in regards to sidewall stiffness.
That's where the smooth ride comes from. On smooth and mildly patchy roads, the DWS smother the bumps excellently.
But big potholes or sharp edged cracks will compress the tire and smack the actual wheel with a nasty thump and bang, and possibly damage the wheel too, if severe
enough. The stock inflation pressure on the front is not enough to prevent this occurrence. Try increasing the front tire pressure to 38psi. 32-35 is too low in front.
It can feel like the suspension is bottoming out, when the tire compresses fully and is forced into the actual wheel/rim.

What is your tire pressure set at? Make sure it is at a MINIMUM of 35 front, 38 rear. Free and easy to do.
If you still have problems, then look at your shocks.

Additionally, with higher psi, you will find that the DWS track srtraight and true through deep puddles of water in the rain.
If too low, the DWS have a tendency to pull the steering wheel as the wheel rolls thru decent puddles of water and certain road contours.

I hope this helps. Let me know.
Appreciate 1
      04-26-2016, 10:19 AM   #3
feuer
Major General
feuer's Avatar
United_States
4289
Rep
9,226
Posts

Drives: wife crazy!
Join Date: Apr 2015
Location: Chicago, IL

iTrader: (5)

Car is 10y old and the struts/shock need replacing, period. Going to 18" just made it obvious! Go with Koni FSD for comfort.
Appreciate 1
      04-26-2016, 12:36 PM   #4
WhiteBeard
Lieutenant
United_States
156
Rep
545
Posts

Drives: slowly
Join Date: Feb 2016
Location: Jacksonville

iTrader: (0)

Thanks guys! The thing is car has only 38K miles, it was rarely used and I think struts are not worn out. I will check my tire pressure and will try to increase pressure to 38psi fronts. Who knows what pressure my local shop put when they changed rims/tires, I bet they put stock pressure.
If that won't help - I'll go with Koni FSD - as I've heard only good things about Koni in general. Thank you again!
Appreciate 0
      04-26-2016, 12:45 PM   #5
pj.rodriguez
Lieutenant Colonel
pj.rodriguez's Avatar
Canada
84
Rep
1,623
Posts

Drives: Alpine White 128i Cabrio
Join Date: Jun 2013
Location: Toronto, Ontario, Canada

iTrader: (9)

Garage List
Go with FSD. They're adorable and a good replacement if you're looking to stay comfortable. Alternatively there are bilstein B4 replacement shocks available, as well as Bilstein B6(HD) shocks available to keep stock height.
__________________
2008 128i E88 / Alpine White / Boston Leather Sport / 6AT / M3 Paddle Shifters / Bilstein B8 / H&R Springs / Dinan Fixed Camber Plates / BMW 335i Front Brakes / PIAA Xtreme White 4150K Angel Eyes / Rear Fogs Enabled / Cyba Air Scoops / Euro Airbox / BMW Performance Exhaust / Stubby BMW Antenna
Appreciate 1
      04-26-2016, 12:56 PM   #6
feuer
Major General
feuer's Avatar
United_States
4289
Rep
9,226
Posts

Drives: wife crazy!
Join Date: Apr 2015
Location: Chicago, IL

iTrader: (5)

Regardless of miles I think they are due for replacement as everything has a shelf life. The struts/shock on newer BMW's are disappointingly short lived.
Appreciate 2
      04-26-2016, 06:16 PM   #7
WhiteBeard
Lieutenant
United_States
156
Rep
545
Posts

Drives: slowly
Join Date: Feb 2016
Location: Jacksonville

iTrader: (0)

Quote:
Originally Posted by thakid22 View Post
Your shocks may very well be worn. How many miles do you have?
But here is something I've found with the DWS on my 535i Sport...
They are very soft, in regards to sidewall stiffness.
That's where the smooth ride comes from. On smooth and mildly patchy roads, the DWS smother the bumps excellently.
But big potholes or sharp edged cracks will compress the tire and smack the actual wheel with a nasty thump and bang, and possibly damage the wheel too, if severe
enough. The stock inflation pressure on the front is not enough to prevent this occurrence. Try increasing the front tire pressure to 38psi. 32-35 is too low in front.
It can feel like the suspension is bottoming out, when the tire compresses fully and is forced into the actual wheel/rim.

What is your tire pressure set at? Make sure it is at a MINIMUM of 35 front, 38 rear. Free and easy to do.
If you still have problems, then look at your shocks.

Additionally, with higher psi, you will find that the DWS track srtraight and true through deep puddles of water in the rain.
If too low, the DWS have a tendency to pull the steering wheel as the wheel rolls thru decent puddles of water and certain road contours.

I hope this helps. Let me know.
Well, I just checked my tire pressure and it was....32 front 35 rear. I bumped both fronts and rears to 38 to see how it goes. So far so good.
Hope it will help, but if not - I'll go with Koni FSD
Appreciate 1
      04-26-2016, 08:58 PM   #8
feuer
Major General
feuer's Avatar
United_States
4289
Rep
9,226
Posts

Drives: wife crazy!
Join Date: Apr 2015
Location: Chicago, IL

iTrader: (5)

Quote:
Originally Posted by WhiteBeard View Post
Well, I just checked my tire pressure and it was....32 front 35 rear. I bumped both fronts and rears to 38 to see how it goes. So far so good.
Hope it will help, but if not - I'll go with Koni FSD
That logic would only work if applied when your tire pressure is too low let say 25psi when there won't be enough pressure and you will be hitting the rims aka bottoming out the tires. Running 35/38 on worn out suspension will make things worse compared to 32/35 as tires will bw more prone to bouncing as they will not absorb the bump as much.
Appreciate 1
      04-26-2016, 10:21 PM   #9
WhiteBeard
Lieutenant
United_States
156
Rep
545
Posts

Drives: slowly
Join Date: Feb 2016
Location: Jacksonville

iTrader: (0)

Quote:
Originally Posted by feuer View Post
That logic would only work if applied when your tire pressure is too low let say 25psi when there won't be enough pressure and you will be hitting the rims aka bottoming out the tires. Running 35/38 on worn out suspension will make things worse compared to 32/35 as tires will bw more prone to bouncing as they will not absorb the bump as much.
I know you are most probably right, it's just me hanging on last hope to avoid going Koni. I just finished doing preventative maintenance (replaced coolant, brakes, all filters, fixed steering angle sensor etc) and wanted to rest a bit before something else comes up It's not just about money, it's just exhausting sometimes, but I guess it's unavoidable.
Any links for Koni FSD and roughly labor estimate? Thank you

P.S. Just wanted to ask, is it a good time to drop the car a bit? Is coilovers what majority use for this? What $$$ I'm looking for 4 corners to drop a bit (nothing crazy, I still want to be able to ride comfortably). Do you guys think lowered pre-LCI 328xi looks better? Thank you
Appreciate 0
      04-27-2016, 12:50 AM   #10
thakid22
Captain
United_States
292
Rep
600
Posts

Drives: 2021 Bmw M340i M-Sport w/ VDC
Join Date: May 2013
Location: Little Rock

iTrader: (0)

Quote:
Originally Posted by WhiteBeard View Post
Well, I just checked my tire pressure and it was....32 front 35 rear. I bumped both fronts and rears to 38 to see how it goes. So far so good.
Hope it will help, but if not - I'll go with Koni FSD
Did your issue improve?
Appreciate 1
      04-27-2016, 09:51 AM   #11
jwebb335xi
Major
United_States
205
Rep
1,070
Posts

Drives: 2008 335 XI
Join Date: Jun 2014
Location: Chicago Burbs

iTrader: (0)

Quote:
Originally Posted by WhiteBeard
Thanks guys! The thing is car has only 38K miles, it was rarely used and I think struts are not worn out. I will check my tire pressure and will try to increase pressure to 38psi fronts. Who knows what pressure my local shop put when they changed rims/tires, I bet they put stock pressure.
If that won't help - I'll go with Koni FSD - as I've heard only good things about Koni in general. Thank you again!
If you replace struts, consider spring pads, bump stops and dust boots. They're relatively cheap wear items though at 38k they may be fine. Also, check the strut mounts. They are about $75 each. I replaced mine when doing struts at 86k, and only one was bad. Thing is, it takes time to get at these parts and I only like to do things once. Others are skilled, work fast or don't mind paying for labor twice. To each his/her own. Just wanted to give you some options to consider.

Working with tire pressures can make a HUGE difference. So thats worth investigating before you pull out the credit card and/or get dirty.
__________________
JWebb335xi

MHD / Wedge / 93 Octane/ xHP / FMIC / Inlets / Catted DPs / CP / DVs
Appreciate 1
      04-27-2016, 07:56 PM   #12
WhiteBeard
Lieutenant
United_States
156
Rep
545
Posts

Drives: slowly
Join Date: Feb 2016
Location: Jacksonville

iTrader: (0)

Quote:
Originally Posted by thakid22 View Post
Did your issue improve?
Surprisingly Yes! I guess 32psi was really low, especially for soft sidewall Conti DWS. I'm just worried about having 38psi in hot summer. I'm moving to Arizona and my 38psi would probably bump up to 40+ no?
Appreciate 0
      04-27-2016, 09:19 PM   #13
jwebb335xi
Major
United_States
205
Rep
1,070
Posts

Drives: 2008 335 XI
Join Date: Jun 2014
Location: Chicago Burbs

iTrader: (0)

Quote:
Originally Posted by WhiteBeard
Quote:
Originally Posted by thakid22 View Post
Did your issue improve?
Surprisingly Yes! I guess 32psi was really low, especially for soft sidewall Conti DWS. I'm just worried about having 38psi in hot summer. I'm moving to Arizona and my 38psi would probably bump up to 40+ no?
Look at tire manufacturer max. I bet it's 50 or so. I ran 38-40 up front for track sessions and autocross. Never any problems with multiple tire types are used.
__________________
JWebb335xi

MHD / Wedge / 93 Octane/ xHP / FMIC / Inlets / Catted DPs / CP / DVs
Appreciate 1
      04-28-2016, 03:02 AM   #14
thakid22
Captain
United_States
292
Rep
600
Posts

Drives: 2021 Bmw M340i M-Sport w/ VDC
Join Date: May 2013
Location: Little Rock

iTrader: (0)

Quote:
Originally Posted by WhiteBeard View Post
Surprisingly Yes! I guess 32psi was really low, especially for soft sidewall Conti DWS. I'm just worried about having 38psi in hot summer. I'm moving to Arizona and my 38psi would probably bump up to 40+ no?
Ah! Great. Now that you know this works, you can play around with the pressures a bit to find the sweet spot for your car.
Appreciate 1
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 07:33 PM.




e90post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST