Resolved - Suspension.....what have I done wrong? - Mercedes Benz SLK Forum

Tires, Wheels, Brakes & Suspension Discussion and information regarding tires, wheels, brakes and suspension.

 40Likes
Reply
 
LinkBack Thread Tools
#1 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Resolved - Suspension.....what have I done wrong?

Well have just completed my revamp on the front suspension and brakes of my SLK230. Everything fine I thought until I lowered the car onto road wheels so I could tighten the various pivoting bush points on the upper and lower control arms. Was I shocked at the 'new' ride height......something clearly isn't right On a positive note I've clearly been consistent in my screw up because both sides are identical!


I have replaced the shocks with Bilstein B4's (24-100878) which are listed as replacements for the standard OEM shocks. I did notice shocks were longer....maybe 1" to 1-1/2" but put that down to the original shocks being shot with very limited travel. I also replaced the upper control arms and fitted new bushes in the lower control arms. I reused the old springs and the upper spring mounts which are 'four dot' which I understand were standard fitment.


Wheel Fender Gap by Gary Laird, on Flickr


Front Right Wheel by Gary Laird, on Flickr


I've seen the questions asked many times on various forums about the 'standard' ride heights of r170 SLK's with no definitive answer. Is there some MB data for this as I have never been able to find? Regardless of that clearly something is wrong


Now my understanding is that only the springs can effect ride height and that any ride height problem can be put down to incorrect springs or poor fitting. I have check and double checked the spring mountings and they are all within a 1/4" of the intended location both upper and lower. I've taken pictures of the lower mount showing spring location but impossible to get any meaningful picture of the upper mounting.


Front Right Lower Spring by Gary Laird, on Flickr


Front Left Lower Spring by Gary Laird, on Flickr


I used some zinc primer to height light the spring ends and pockets so they could easily be seen during installation.


The only other possible issue was that after replacing the lower control arm bushes the refitting was tight and the had to be knocked back into place so I could insert the long bolts through the bushings. I had use rust treatment and underseal to clean things up when the wheel well was totally clear so not surprised things were a bit sticky going back in. Having said that, once installed I was operating the lower control arm by hand when installing the rest of the suspension components so they were not seized or bound in any way.


Other than that, the car has been up on axle stands for the last two months front and rear together. In the pic above I used wooden blocks under the wheels while the rear is still up on axle stands. At that the car is fairly level.


So I am at a lost to understand what I've done here. Any ideas/suggestions?

Last edited by Avel Du; 02-09-2019 at 11:33 AM.
GaryLaird is offline  
Sponsored Links
Advertisement
 
#2 Old 12-20-2018
Premium Member
 
Windinmyhair's Avatar
 
Join Date: Sep 2017
Location: Cotswolds
Vehicle: 2014 SLK r172 200AMG blue efficiency petrol Auto
Other Toys: Lots of tools
Posts: 1,582
Country:
Chats: 0
Mentioned: 22 Post(s)
Tagged: 0 Thread(s)
Quoted: 328 Post(s)
Thanks: 56
Thanked 135 Times in 130 Posts
Can you check the actual height of the car Gary?

Mercedes-Benz SLK-Class (R170)
Width 1,715 mm (68 in)
Height 1,289 mm (51 in)
Kerb weight 1,195–1,461 kg (2,630–3,220 lb)
Avel Du likes this.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Windinmyhair is offline  
#3 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
@stu32 on an earlier thread you had mentioned replacing your suspension with Bilstein B4's. Do you still have note of the Bilstein part number you used for the fronts?
GaryLaird is offline  
 
#4 Old 12-20-2018
Registered Users
 
Join Date: Oct 2018
Location: Navarre, Fl
Vehicle: 2003 SLK230
Posts: 30
Country:
Chats: 0
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Thanks: 1
Thanked 3 Times in 3 Posts
Garage
For starters, it is probably experiencing camber push. That is, when you let the weight back onto the road wheels the tires could not "slide" outwards allowing the suspension to relax. On the floor, we roll it back and forth a foot or two to allow the vehicle to settle. As far as specs goes, I found a thread over at benzworld about it. If I'm a bad guy for linking it, break out the wet noodles.



https://www.benzworld.org/forums/r17...k-sport-2.html
jbanks15, Avel Du and Windinmyhair like this.
Bamanut is offline  
#5 Old 12-20-2018
Administrator/Founding Member

 
jbanks15's Avatar
 
Join Date: Jun 2006
Location: Valrico, Florida
Vehicle: 2009 SLK 55 AMG Kleemann Supercharger, ECU tune, Headers and LSD, CF Diffuser
Posts: 90,422
Country:
Chats: 38
Mentioned: 445 Post(s)
Tagged: 5 Thread(s)
Quoted: 6442 Post(s)
Thanks: 3,218
Thanked 10,964 Times in 8,329 Posts
Not for linking, not signing up for the Florida Meet!
M4rCu5 and Bamanut like this.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Jeff, US Army Master Sergeant Retired
2009 SLK 55 AMG Black/Black
Kleemann Supercharger thread here:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Kleemann ECU Tune, headers and downpipes thread here:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Albums:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

ClearBra
OEM MB Plexiglass Draught Stop
Smarttop version 3.22
Previous - 02 SLK 320, 05 SLK 350
jbanks15 is online now  
#6 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by Windinmyhair View Post
Can you check the actual height of the car Gary?

Mercedes-Benz SLK-Class (R170)
Width 1,715 mm (68 in)
Height 1,289 mm (51 in)
Kerb weight 1,195–1,461 kg (2,630–3,220 lb)

Right, assuming this is from ground to the highest point of the car. Hard to do with any degree of accuracy as car is up on blocks/stands so a lot of 'eye balling' but I get to 52-/2"
GaryLaird is offline  
#7 Old 12-20-2018
Premium Member

 
Turdo2's Avatar
 
Join Date: Apr 2013
Location: Kansas
Vehicle: 1999 SLK 5.4 M113 V8
Other Toys: Ram 2500, Plymouth Duster
Posts: 1,299
Country:
Chats: 0
Mentioned: 377 Post(s)
Tagged: 1 Thread(s)
Quoted: 346 Post(s)
Thanks: 0
Thanked 76 Times in 68 Posts
Garage
You need to put all the weight of the car on the wheels and move it around. My guess is everything is fine.
Avel Du and Windinmyhair like this.
Turdo2 is offline  
#8 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by Bamanut View Post
For starters, it is probably experiencing camber push. That is, when you let the weight back onto the road wheels the tires could not "slide" outwards allowing the suspension to relax. On the floor, we roll it back and forth a foot or two to allow the vehicle to settle. As far as specs goes, I found a thread over at benzworld about it. If I'm a bad guy for linking it, break out the wet noodles.



https://www.benzworld.org/forums/r17...k-sport-2.html

Thanks @Bamanut for that link. This confirms that the 4 knob spacer is 17mm. While I could understand that suspension would need to settle/readjust and rolling car back and forth would potentially drop the car a few mm it seems to me, just by appearances that suspension needs to drop around 3" Wish I had measured the old setup before I started but I do have this old pic which was intended to show the rust problem but it clearly shows the massive different in the tyre/fender spacing.


IMAG0401 by Gary Laird, on Flickr
Bamanut likes this.
GaryLaird is offline  
#9 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by Turdo2 View Post
You need to put all the weight of the car on the wheels and move it around. My guess is everything is fine.

Thanks @Turdo2, wish I could share your optimism . If you look at the picture of the old 'before' picture I just posted you can see there is a massive difference. Really can't imagine the suspension would really settle that much. Having said that I am totally stuck as to what else could be causing this.
GaryLaird is offline  
#10 Old 12-20-2018
Premium Member
 
Delucas's Avatar
 
Join Date: Aug 2012
Location: KENT
Vehicle: MERCEDES SLK 171 - 09. - SLK KENT GROUP MEET - EVENT ORGANISER
Posts: 4,788
Country:
Chats: 0
Mentioned: 188 Post(s)
Tagged: 0 Thread(s)
Quoted: 1132 Post(s)
Thanks: 52
Thanked 343 Times in 321 Posts
Garage
Regardless before you can move forward is lower car to ground
Drive car let suspension settle down .
Then go from there .


You still have the car jacked up !

So no weight of car on suspension components !
Avel Du likes this.
Delucas is online now  
#11 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by Delucas View Post
Regardless before you can move forward is lower car to ground
Drive car let suspension settle down .
Then go from there .


You still have the car jacked up !

So no weight of car on suspension components !
Sorry, not sure I understand what you mean, the weight of the front of the car is on the wheels, at least the fronts are. The car is resting on the front wheels and rear axle stands. Anyway I don't want to tighten up the bushings until I get the level as close as possible to that expected. Is it OK to drive with the bushing bolts loose?
GaryLaird is offline  
#12 Old 12-20-2018
Banned
 
Join Date: Oct 2017
Location: Waynesville, OH
Vehicle: 2010 Silver SLK 350
Other Toys: BMW 135i and big fat grouchy black cat!
Posts: 330
Country:
Chats: 0
Mentioned: 19 Post(s)
Tagged: 0 Thread(s)
Quoted: 108 Post(s)
Thanks: 0
Thanked 25 Times in 25 Posts
Thumbs down What a screw up!

The correct ride height is easy to determine, two to three fingers between the top of the tire and the fender rim.

The shocks should be the same length. There just isn't that much movement in any shock, new or old. You should have carefully compared them and made sure there wasn't any mistake in the part numbers.

All suspension components should freely move up or down. The control arm you replaced may be a bit stiff, but they should freely move with a little force on them. Did you use a torque wrench? They may be binding? The springs may not be properly seated.

Finally, with the full weight of the car resting on the suspension, just how bad is the gap? You might drive the car around the block and hit a few bumps. If the suspension doesn't settle down correctly, you did something wrong. I'd suspect the shocks. If you can, examine if the springs are being compressed. Jack a corner up and let it down. Examine the gap between adjacent spring coils.
SilverSLK2010 is offline  
#13 Old 12-20-2018
Registered Users
 
G0RSQ's Avatar
 
Join Date: Oct 2017
Location: Northwest England, Near Liverpool
Vehicle: SLK 350 2007, Auto, Silver, Red leather, SmartTop, COMAND, AirScarf, Heated Seats, grin factor
Other Toys: MG TF and 2 x Ducati 750's (MGB under long term restoration!)
Posts: 447
Country:
Chats: 0
Mentioned: 23 Post(s)
Tagged: 0 Thread(s)
Quoted: 151 Post(s)
Thanks: 19
Thanked 75 Times in 52 Posts
The shocks will not affect ride height, unless they are faulty (no movement), or have bottomed out! Only springs affect ride height.


I agree that the suspension needs to settle, and car must be on ground and pushed back and forward a few meters (yards) so wheels settle to correct track.


Then try bouncing the suspension to prove there is movement in the shocks/suspension links.


If suspension is moving, and ride height is still way too high, then springs must be wrong, or incorrectly fitted.


If ther is no movement in suspension, then either suspension arms/links have been fitted incorrectly (and locked up), or shocks are faulty/wrong/damaged
G0RSQ is offline  
#14 Old 12-20-2018
Registered Users
 
Join Date: Sep 2017
Location: Orlando
Vehicle: 05 SLK55 & 06 Kleemann 55K S8
Other Toys: 335Xi (modded) Suzuki GSXR1000
Posts: 674
Country:
Chats: 0
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Thanks: 4
Thanked 59 Times in 59 Posts
Try to measure how far up the upper spring perch is on the new struts versus the old ones. Maybe they put the perch in the wrong spot or they are the wrong struts?
jet_fl is online now  
#15 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by SilverSLK2010 View Post
The correct ride height is easy to determine, two to three fingers between the top of the tire and the fender rim.
Right and I have a whole hand in there with still more space available!


Quote:
Originally Posted by SilverSLK2010 View Post
The shocks should be the same length. There just isn't that much movement in any shock, new or old. You should have carefully compared them and made sure there wasn't any mistake in the part numbers.
Not if the old shocks were screwed! On @S/RConcepts suspension rebuild thread here https://www.slkworld.com/general-mod...esh-slk32.html he noted exactly the same that his Bilstein shocks were longer on the front than original but in his case ride height did not change. What makes you think I did not check part numbers? The MB OEM part # for these is A1703200130 which is given on the Bilstein site as well as other suppliers site as 24-100878 for the B4 shocks. So short of Bilstein putting the wrong shock in the wrong box I'm pretty sure its not wrong!

Quote:
Originally Posted by SilverSLK2010 View Post
All suspension components should freely move up or down. The control arm you replaced may be a bit stiff, but they should freely move with a little force on them. Did you use a torque wrench? They may be binding? The springs may not be properly seated.
Yes suspension parts move although, as I noted above, the lower control arms were more than a push fit to get them in place. I have not torqued the bushing pivot points yet, wanting to get the ride height correct before I do that. The springs not being seated is something I've checked 3 or 4 times and I can't see anything wrong. From the pics above you can see, at least the lower seats, are in the correct place.....more or less!

Quote:
Originally Posted by SilverSLK2010 View Post
Finally, with the full weight of the car resting on the suspension, just how bad is the gap? You might drive the car around the block and hit a few bumps. If the suspension doesn't settle down correctly, you did something wrong. I'd suspect the shocks. If you can, examine if the springs are being compressed. Jack a corner up and let it down. Examine the gap between adjacent spring coils.
Well with the front wheels carrying the weight of the front of the car you can see from pic above that I can get my whole hand in there and then some as well as the dimensions I gave. While I understand suspension will settle it would need to settle around 3" to get back to where it was before. Maybe having the rear on axle stands effects all this but I would have thought two wheels and two axle stands would generate the same load on the wheels as if the car was standing on all four wheels? Springs are compressing under load that's for sure.
GaryLaird is offline  
#16 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by G0RSQ View Post
The shocks will not affect ride height, unless they are faulty (no movement), or have bottomed out! Only springs affect ride height.


I agree that the suspension needs to settle, and car must be on ground and pushed back and forward a few meters (yards) so wheels settle to correct track.


Then try bouncing the suspension to prove there is movement in the shocks/suspension links.


If suspension is moving, and ride height is still way too high, then springs must be wrong, or incorrectly fitted.


If there is no movement in suspension, then either suspension arms/links have been fitted incorrectly (and locked up), or shocks are faulty/wrong/damaged
Yes, as I have read, the shocks should not effect the ride height but its the only unknown factor in all of this since I'm using the original springs. If I bounce the car there is movement in the suspension as you would expect...so that all seems normal. Agree that everything points to the springs being incorrectly installed but I'm blowed if I can see what's wrong. Maybe because only front wheels are under load and the rear is on axle stands then this is doing something to the overall suspension loading and giving false impression. I have the rear suspension to do next so I think I will get on with that then be able to get the car on the road to get a true feel for where the ride height is at
GaryLaird is offline  
#17 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by jet_fl View Post
Try to measure how far up the upper spring perch is on the new struts versus the old ones. Maybe they put the perch in the wrong spot or they are the wrong struts?
Hi, the r170 uses separate springs and shock absorbers not struts (spring/shock) combination units.
GaryLaird is offline  
#18 Old 12-20-2018
Registered Users
 
Join Date: Sep 2017
Location: Orlando
Vehicle: 05 SLK55 & 06 Kleemann 55K S8
Other Toys: 335Xi (modded) Suzuki GSXR1000
Posts: 674
Country:
Chats: 0
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Thanks: 4
Thanked 59 Times in 59 Posts
Quote:
Originally Posted by GaryLaird View Post
Hi, the r170 uses separate springs and shock absorbers not struts (spring/shock) combination units.
My mistake, I thought it was an R171. Have you tried putting the car down and putting weight on the front (press on it and try to get it to move)? Maybe the shocks are just stuck.
jet_fl is online now  
#19 Old 12-20-2018
Registered Users
 
GaryLaird's Avatar
 
Join Date: Jun 2018
Location: Falkirk, UK
Vehicle: 2010 SLK350 r171
Posts: 353
Country:
Chats: 0
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 111 Post(s)
Thanks: 8
Thanked 24 Times in 19 Posts
(Thread Starter)
Quote:
Originally Posted by jet_fl View Post
My mistake, I thought it was an R171. Have you tried putting the car down and putting weight on the front (press on it and try to get it to move)? Maybe the shocks are just stuck.
yes for sure, I've been bouncing it up and down but it does not seem to help, no noise, creaking. Everything seems to work as it should just the bodywork seems very high over the wheel. I've not got it on the ground, just front wheels on wooden blocks.
GaryLaird is offline  
#20 Old 12-20-2018
Registered Users
 
Join Date: Sep 2017
Location: Orlando
Vehicle: 05 SLK55 & 06 Kleemann 55K S8
Other Toys: 335Xi (modded) Suzuki GSXR1000
Posts: 674
Country:
Chats: 0
Mentioned: 6 Post(s)
Tagged: 0 Thread(s)
Quoted: 205 Post(s)
Thanks: 4
Thanked 59 Times in 59 Posts
Check out the swaybar, is that all installed correctly? If incorrect that could affect ride height as it will apply pressure to the A arm just like the springs.
jet_fl is online now  
Sponsored Links
Advertisement
 
Reply

  Lower Navigation
Go Back   Mercedes Benz SLK Forum > Technical Information > Tires, Wheels, Brakes & Suspension

Bookmarks

Quick Reply
Message:
Options
Upload your files to MEGAUPLOAD
Upload your images to ImageShack

Register Now



In order to be able to post messages on the Mercedes Benz SLK Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
User Tag List

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Time for a new suspension? conleyjb Performance MODS for the R170 19 06-03-2019 12:07 AM
SLK350 Suspension fitted, 2 Broken Springs. Grandpa Munster Tires, Wheels, Brakes & Suspension 11 01-08-2018 12:03 PM
F1 teams back active suspension return Berliner Heckflosse Motorsports 2 02-19-2017 03:30 PM
help on slk 200 r171 suspension. wrx_sti10 Tires, Wheels, Brakes & Suspension 3 03-17-2015 11:15 AM

Posting Rules  
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome
 

Clubs, Garage Plus vBulletin Plugins by Drive Thru Online, Inc.