S-Prihadi

The fuel cap reccomendation is too much, for me. Equal to like 40 psi at the rear if fully loaded.
Daily when i don't do long trip loaded, I use only 32psi front , 33 psi at rear.
Long trip loaded people and cargo at 350kg approx including me , at best 34psi all around with 10 hours non stop run, except fuel stop and lunch.
Only track use I do 36 psi rear and 34psi front, around there.

rapidoxidation

Not sure if I mentioned my pressures: I was kinda high with 40 front 44 rear cold, and the instrument cluster said that they were closer to 44 front 48 rear when running with the full load at 80mph for thousands of miles. I REALLY didn't want a pothole to destroy a rim a long ways from home, and if that costs a set of tires then so be it.

rapidoxidation

Just got off the phone with Kevin and pulled the trigger on his kit 502126K lower control arm kit to address the tire issue. Parts should be here Friday and I'll install 'em next weekend. Hopefully my local alignment shop can get me in for an alignment before we leave for a thousands-of-miles trip for Thanksgiving...
Thanks @K-Mac !

YAOG

AFAIK there is no reason to need more adjustment than is stock unless the chassis and/or suspension control arms are damaged - or this is for a race car.

All this tire cupping is caused by worn out bushings and ball joints. If you have a W212 chassis with over 50K on your front bushings they are getting close or already worn out or damaged. The rear 5-link is usually good for about double so approx. 100K. The Mercedes chassis is just like a BMW chassis, all the rubber and hydro bushings are soft for comfort and isolation but for a driver they are way too soft allowing too much movement under even normal driving stress.

With the S212 up on the 2-post a very careful visual inspection of my 70K S212 4MATIC showed perfect bushings but there was a surging, sometimes oscillation steering feel when accelerating or braking. This is exactly the same way my BMW E61 530xi felt and the suspension is basically the same design. The known cure is replacement of the front upper/front lower control arm. Inspection also showed that the front lower/rear control arm ball joints were worn so I did all four control arms - problem solved. This S212 Sport Wagon had all of its original control arms and when I removed and inspected them the rubber parts looked perfect. But Mercedes uses a hard plastic gap filler to limit fore-aft movement of the control arm and the hard plastic fillers were broken off causing the excessive movement I was feeling while acerating or braking.

The lesson here is you cannot really rely on a visual inspection for this type of bushing unless they are obviously leaking or the rubber has let go and broken. You must drop the chassis side and inspect the hard plastic gap fillers to see if they are still present. But if you have gone this far already you might as well just replace them all. The same applies to the rear 5-link setup which has worse inspection working room and as I learned in this W212 4MATIC Wagon you cannot rely on an in chassis visual inspection for a chassis with this type of bushing with directional stiffeners.

CaliBenzDriver

thank you for sharing your experience with these control arm slotted bushings that look decively better than they actually are. They age by getting gradually softer over time.

Have you had to deal with the Front/Rear subframe slotted bushings getting soft as well?

How long would you say is their usefulness: 50 or 100 or 150K ? (I am currently discovering that problem with my daily driver after swapping control arms)
✌️

S-Prihadi

YAOG wote :
"But Mercedes uses a hard plastic gap filler to limit fore-aft movement of the control arm and the hard plastic fillers were broken off causing the excessive movement I was feeling while acerating or braking."

Any photo of this plastic gap filler ?
I have not messed with my rear suspension links much, only the front ones when I was using correction caster/camber bolts from MB to get the alignment properly back in spec.
Thanks

rapidoxidation

The kit arrived today - a week later than anticipated. Given that the alignment is scheduled for tomorrow morning at 10AM and I'm leaving for a few thousand miles on Friday, I only had time to install the camber adjusters. Left the toe adjusters off because there's nothing wrong with that, but if I need to put them on at a later date I'll do so.
Hopefully Daniel the Alignment Guy will be able to bring things to where they need to be.

rapidoxidation

Fresh continental extreme contact sneakers (siped) and a 4 wheel alignment. Rides like it's on glass at jailtime speeds. Everything is in the green. Love it!

up_too_late

Looks like I’m going to be added to the list of those with excessive passenger rear inner tire wear. I pulled the wheel to investigate loss of tire pressure and found the inner worn past the belt. I have driven 6,000 miles in the past several months, some heavily loaded on highway (4 passengers plus lots of luggage). I’ve been running 41 in the rears so maybe too low for that load. I did put new air springs in the rear this year, but ride height is the same before and after. The right seems to be 5mm higher than the left, but could also be my garage floor or that only the driver was in it last. Either way it was that way both before and after new air springs.

Any suggestions other than new tires and alignment? My understanding there isn’t much adjustment in the rear. Should I look into eccentric bolts or whatever?

CaliBenzDriver

this extreme wear patern looks like it's a call for action. It's only on one wheel, not both rear right?

I am dealing with exact same thing on my DD....

shaved inner edge
​​​​​​
This tire wear patern shows it is driving over its edge instead of flat on center section - How can this be so extreme ??

Everbody usually goes for control arms, ball joints and toe alignment to find the camber a little off but not much. 6 month later the new tire already looks sorry.... Again!?

Realize the engine power from the wheels doesn't directly push the chassis.
The lower control arm power acts on the sub-frame to push the chassis. In other words the subframe bushings work hard.

relief slots for gentle motions

They are made with relieve openings to provide soft ride unlike solid polyurethane.

Old sub-frame bushings allow too much freeplay. The sub-frame looseness tweeks both the camber and toe when under torque.

The alignment station can't pick up on this issue when the loose sub-frame bushings are resting near neutral position. As soon as engine torque is applied wheel geometry goes side ways

pic -- non MB sample:

typical subframe bushings

let me try to fetch a view of MB subframe setup.
Here....

spare parts tree location...

W212 "cross-member": rear sub-frame bushings


W212 "engine cradle": front sub-frame

K-Mac

THE PROBLEM IS BASIC, ELEMENTARY - OEM THERE IS NO CAMBER (OR CASTER) TO ADJUST TIRE CONTACT ANGLES SPREAD LOAD MORE EVENLY!

Essential to cater for day to day commuting encountering high cambered roads with excess inner edge tire wear on right hand side. Or wheel squat through load carrying or lowering. Fitting wide profile tires or just having ongoing adjustability to cater for curb knock damage.

IT IS NEW CAR INDUSTRY'S BEST KEPT SECRET. ALL TO DO WITH COST CUTTING AND EVER INCREASING SPEED OF AUTO ASSEMBLY LINES.

The often quoted reassuring "we will carry out a Full Front & Rear 4 Wheel Alignment" in fact is only Toe (directional) adjustment

Align tech can adjust front and rear Toe all he wants. But issue is not resolved then trying to placate, justify by stating "is within factory specs

We saw the need therefore to re instate once again from the early 90's Full front and rear adjustment. Front Camber (and also Caster). Rear Camber (and extra Toe).

SEE SPOILER - W212/S ALL E200-550, E63, E65 AMG






AUDI to VOLVO - K-MAC Experience Of Resolving OEM Suspension Shortcomings Since 1964 !

S-Prihadi

K-Mac,
Some questions if I may...

This W212 bushing kit set for rear : https://k-mac-camber-kits.com/produc...t12-502628k-1/
and
Front adjustable bushing kit : https://k-mac-camber-kits.com/produc...shing-502916k/

How much harsher are they compared to standard bushing MB is using ?

I am not after a harsh ride but the front being adjustable is quite nice. The MB original camber & caster correction bolt is 1 value only, no adjustment flexibility.

Thanks

up_too_late

Correct, it is only the passenger side rear. The driver side rear is worn but not to this extent, it measures 5mm on the outside and 3mm on the inside. This seems pretty reasonable to me as looking at a tire with 5mm depth I'd think the tires need to be replaced soon but it's not urgent. Then on the passenger rear is 4mm on the outside and what looks like a -1mm or worse on the inside, and it's gone beyond dangerous.

IIRC these tires are symmetrical so were cross rotated, fronts to opposite rear and rears to front. I measured the snow tire that last came off from this corner and it is 8mm on the outside and 5mm on the inside. Those tires are directional so they are only rotated on the same side. I average 8,000 miles a year and those miles are split across all-seasons and snow tires, so I haven't bothered tracking tire rotations as it's unlikely I'll hit 5,000 miles before I have to swap the tires over.

I am going to start with new tires and alignment, up the rear pressures from 41 to maybe 45, and monitor closely. Maybe the alignment will show something. I don't want to have to become like S-Prihadi and obsess over every detail and measure tire depths at a dozen locations every 5 miles , but likely I'll keep a spreadsheet of tire depths monthly and track mileage and tire change overs more closely. If I continue to see excessive wear maybe the next step will be replacing the control arms. I don't want to get into dropping the subframe until I really have to (when it eventually rusts out).

EuroDriverSD

I can vouch for the K-Mac bushings. I installed them on my lowered W212 and it aligned perfectly and no more wear on the inner edges of the rear tires.

I had them installed at a high end suspension and alignment shop and they commented that they have installed quite a few similar adjustable bushings but the K-Macs are the best they've ever seen

K-Mac

Yes the OEM front bolt only provides one offset position .3 of one degree (1/8"). KMAC design provides serious adjustment 4 times the range and is precise single wrench accurately under load - direct on alignment rack!

While the uprated bushing kit for the rear suspension came about through so many AMG owners complaining of excess rear end twitch, breaking traction when power was applied.

Especially when lane changing and accelerating.

P/N 502628L kit uprates the 6 rear multi link arms OEM soft rubber mount bushings and provides quite significant, noticeable improvement.

Re the Front Camber and Caster adjuster kit (P/N 502916K). The OEM Caster bushes are large 70mm diameter soft rubber, oil filled and air voided.

Most after market brands replace these bushes with urethane for tauter response, reduced flex.

But problem is today's auto's - multi link arms, different mount angles it is essential that arms can still travel through their required suspension arcs without binding, locking up.

Unique design KMAC bushes therefore not only are Caster adjustable but also Monoball / 2 Axis self aligning and like OEM allowing arms to travel through their required suspension arcs.

Yet significantly improving brake and steering response without the unforgiving harshness of urethane or spherical bearings

-Kevin

S-Prihadi

Thanks Kevin of K-MAC ....
Awesome info.

Now, some more questions to make sure I do not make compatibility mistake when I buy your kit.
We shall discuss this here so that other members can have the information too


01. Which one is the correct one, photo showing 18 pcs of bushing or the installation sheet stating 16 bushes ?




02. The dimension of your bushes, I am sure I will use the millimeters ones because the US/imperial dimension stated does not make sense as an example : 4/43 OD if inch means 2.36mm only
Bush mount positions :
AA. I believe these millimeters value are all OD measurement correct ?

BB. 43mm, 39mm and 38mm all 4 each. <<<< the one on the photo if the scale is correct, the smallest one is no way a 38mm and seems to be all metal and no rubber/polymer
Can you show the actual photo of what I will get for 502628K rear bushing kit ?


===========================================

Kindly show me which are the K-MAC bushings I will get to replace original ones.

03. The so called spring control arm item 120, has item 40 as its bushing on wheel knuckle/carrier and surely on the subframe side too of same size. So left and right rear suspension uses 4 of item 40 which is P/N A204 352 00 27.






04. This one is item 50 bushing , P/N A205 352 05 08. MB call it Thrust Arm or Control Arm or Pushing Strut ...LOL , must be 3 different engineers way of naming parts.
So left and right rear suspension uses 4 of item 50.








05. Item 250 , 350 and 450. I hope I number them correct.
Per side will have 6 bushings, for Left and Right suspension therefore 12 pcs. I do not know if they are all same bushings or not










Summary :
For LEFT and RIGHT Rear Suspension

Item 50 P/N A205 352 05 08 .. 4 pcs
Item 40 P/N A204 352 00 27 .. 4 pcs
No P/N for bushings stand alone. .. 4 pcs for item 250
No P/N for bushings stand alone. .. 4 pcs for item 350
No P/N for bushings stand alone. .. 4 pcs for item 450

Total 18 pcs.


So what goes where exactly ?
I only have worked on front arms when I installed caster/camber correction bolts, I never mess with the rear ones....yet.



Can you show me the 3 items named on your BUSH MOUNTS POSITIONS , to the actual arms as per MB EPC ?

There are 5 arms on the rear suspension.
Item 120 where the rear spring is at.
Item 540, in ugly steel, painted black, called thrust arm
Item 450, tie rod, where I adjust the toe.
Item 350 strut rod
Item 250 camber arm




My car is W212.065 E400 of 2014, RWD, Right hand drive.


Thanks so much Kevin.

S-Prihadi

Assuming that I get to replace all my rear suspension bushings using K-MAC 502628K 100% compatible, here is the financial consideration for MB members considering the same.

Labor of arms removal and old/new bushing remove-install is not included.

My price reference using this company : https://www.ssg.asia/ because they are the lowest $$ and has so much parts. Me not in USA too. I also wants 100% genuine.
Lemforder for me, I will avoid at all cost. My unpleasant experience with their JUNK rear damper top mount is more than enough.


A is if you are lucky and get can 3rd party bushings for item 250, 350 and 450. I placed US$15 value per bushings.
B is the most likely scenario
C is what K-MAC offers, well kinda expensive but for desperado.... is a better choice than B, if there is no accident on the car and only bushings get "tired". Mild extortion hahahaha. No offence Kevin, its just a joke.




My car now at 36,000KM and 8 years old bushings, will need option C perhaps before it hits 50,000KM or a good reward/present for the car by year 10th. I do at most 5,000KM a year, usually much less now.
Come 10th year Bday, all 4 subframe mounts as shown by Cali need to go too, to make certain car will not reach a stage where Cricket Concert will occur.
Cricket Concert is the term I use when a car is aging and every damn things started to creak and make those cheap junk car sound an MB should not be doing.
I once abused a 1.0 liter Toyota Starlet to a point its monocoque/chassis weakenedd and when I do hard cornering the rear door light will turned ON itself due to flexing and the door light switch activated... LOL.
This little Toyota super reliable el-cheapo get new clutch ( manual tranny ) and engine mounts per 20,000KM because they are gone by then...I mean engine mounts will knock loud ...ha ha ha.

I have planned to replace the 4 subframe mounts since 2019, but when is the good time to do it other than year 10th, is still "sensing" in progress, as the Cricket Concert participants have
not arrived yet . If i do total rear suspensions bushings replacement, 4 sub-frame mounts get some love too then and 2 bushings for the Differential too. I already have new differential middle mount at hand.

By alignment value, my rear RIGHT suspension camber is soon reaching its limit. Only another 6 minute of a degree away or 0.1 degree, so K-MAC option C is a good candidate to freshen up all the bushings and
get the alignment values and comfort and silence back to as-new-as-possible.

=============================

Rear-Subframe Mounts

Photo below, its 12 o'clock is heading to front of car.



The front side mounts 11 and 1 o'clock.








The rear side mounts, 7 and 5 o'clock.



Close up using Meyle datasheet



==================

DIFFERENTIAL


Bushings for Differential. Item 50 x 2 units. Item 200 is the small mid mount, 1 unit , which I already have in hand since last year.

K-Mac

Re "now some more questions"!

Goodness idea of instruction sheet was to "simplify" not to have to refer to factory diagrams or cross reference. But to provide a logical, systematic installation step by step procedure including:

Parts enclosed, Bush mount positions and step by step fitting.

GOING THROUGH MANY OF YOUR QUESTIONS.

Picture contains a total of 12 bushes:
- 1st row of '6' depicts outer sleeves.
- 2nd row inner crush tubes for these outer sleeves
- 3rd row complete (with crush tubes and outer tubes).


Re instruction sheet Parts enclosed - 12 plus 4 (16).

Actual quantity 12 - the 4 other items are end caps, not bushes!


NOTE INSTRUCTION SHEET BEEN SUPERCEDED (see new current sheet attached).


ALL BUSH SIZES MENTIONED ARE METRIC (43mm OD, 39mm OD, 38mm OD).


Re # of bushings.

As stated kit replaces the '6' main multi link rear arm bushings (12).

Rear suspension contains another '4' arms.
2 'main' lower control arms and the 2 'Toe" adjustable arms.

To complete the uprating of all bushings the KMAC rear Camber and extra Toe adjuster kit replaces the 4 main bushes in these 4 remaining arms (502226K).

Your mention of uprating the rear 4 main subframe bushes.

KMAC P/N 503028Q. Kit is also supplied with bush extraction tool so not requiring the purchase of expensive tools (or the time consuming fabrication). AND ALSO DESIGNED SO BUSHES CAN BE REMOVED ON VEHICLE WITHOUT NEED FOR SUBFRAME REMOVAL!

Also manufacture the 2 DIFF mount Bushes (Monoball / 2 Axis self aligning P/N 503228J).

Click here re uprated rear bushings instruction sheets ( Multi link arms, Subframe & Diff.)

S-Prihadi

Thanks Kevin.

============
Re instruction sheet Parts enclosed - 12 plus 4 (16).

Actual quantity 12 - the 4 other items are end caps, not bushes!
============
My bad, sorry.


Update your website with the new Installation Manual please.
Don't be lazy, please write this way to avoid mistake for PARTS ENCLOSED
12 pcs : 4 of 43mm O.D , 4 of 39mm O.D and 4 of 38mm O.D
=== 4/43mm now that you have added mm , still can mean division for the slash "/" ====

You must assume all buyers are non-knowledgeable, albeit the workshop is knowledgeable. The $$ to you come from the buyer, not the workshop.




===========
Goodness idea of instruction sheet was to "simplify" not to have to refer to factory diagrams or cross reference.
===========

This is where you assumed too much, because you are the designer and is an expert in the field and knows so much....but we don't.
Any careful buyer like me, will first try to at least measure the OD of all the bushings on the car to compare if the OD matched to your Parts Enclosed. I would even go to measure ID of the crush tubes.
MB often updated its parts and I can not risk making a mistake on bushing size and more so on the facelift model starting 2014, where many small changes occurs.
This is why I wanted you to tell me which control arms as per MB EPC I posted, the 3 sizes bushings goes to , so that I can verify. This is a normal request.


==============
Picture contains a total of 12 bushes:
- 1st row of '6' depicts outer sleeves.
- 2nd row inner crush tubes for these outer sleeves
- 3rd row complete (with crush tubes and outer tubes).
===============


Thank you... I forgot that your design for item 1 and 2 is "sport" type. I hope that is the "correct" term.


This design 1+2 is not suitable for me.
This one I have to do lubrication maintenance once per 1 ish or 2 years to lubricate the item 2 ( crush tubes ) interface to the rubber/PU (whatever the material you use ) because crush tube is spinning type and
not the "dead" molded type of OEM ones.

I understand for sportier driving this is good design. The lubrication maintenance for squeak free operation is not something I want to put up with, as these arms have no grease jerk fittings like
off road cars using Total Chaos control arms my friend's Toyota Fortuner is using.... which no way a luxury sedan will have such grease fitting


Is the number 3 bushing a dead molded one to its rubber or removeable crush tube one ?

.................................................

For MB members, here is what I mean by squaeking


Comfy bushing gets its inner crush tube molded/dead into the rubber and it twist the rubber, like below :
Less precision, rubber will get damaged eventually... but comfy. Comfy has a price.


Thanks again Kevin, for all the valueable information

K-Mac

Ok updating instruction sheet for the rear uprated bush kit for the ‘6’ multi link arms now deleting the slash !!

Re bushings must point out KMAC has the experience of manufacturing performance bushings for Street or Track longer then any one else 58 years (1964). Designs tested proven to outperform short life urethane, delrin or spherical bearings.


-Kevin

up_too_late

Attached are the alignment results, if it weren't confusing enough.

S-Prihadi

Where is the alignment report image ? All I see is NO ENTRY sign

up_too_late

Strange. I see it on a PC but not mobile. Here it is again.


My current thought is to monitor the wear and replace the rear control arms at some point to eliminate potential for bad bushings. This report shows the driver side having more camber but the wear is more acceptable on that side. In my mind that leaves either a bad tire (or pressure) or bad bushings. Or the alignment report is wrong. This was done at an indy shop, so I doubt they measure ride height from the axle. I'm not shooting for exactly even wear.

S-Prihadi

Your car is 4matic and some values are different than mine.
Attached full alignmet data and make sure you have your data card for suspension type.

No way any alignment machine will keep the database this complete.
So you make your own list, like I do and I supervise the value I want at the alignment shop.

Your Indie is lazy for front toe. For me, I insist that it is to be near equal spacing of say 60/40 and not like your front Toe where LEFT takes all the setting and RIGHT is zero.
Yes, 0.10 degree is a bi-etch to spread between Left and Right, but its only extra 3 minutes.

Remember, Mercedes WIS alignment data is Decimal Minutes. Your alignment result uses Decimal Degree, find below the conversion .
Romess value is Decimal Degree


Your car in red box below.



Happy troubleshooting........

Left Coast Geek

also these cars are supposed to be aligned via the 'spreader bar' method.

now, I've never had it made clear to me just what that means... where/when is the bar applied and how?