splinter

Because my W203 has accumulated more than a few miles and its steering felt as if it had lost some of its precision and tracking confidence, it was readily apparent that something was amiss. Since the torque and thrust arm bushing replacements had already been completed, the search was on for the next culprit...sure enough, the source of its numb front end feel, particularly over single-wheel irregularities, was the (#115) strut bearings.

To replace them is an easy and inexpensive task.


Get with your preferred parts purveyor to obtain:

(2) 203 320 02 73 Suspension strut bearing
(2) 203 320 00 56 Strut mounting kit
(2) 203 320 08 44 Rubber buffer
(1) 203 589 00 07 00 Strut retainer tool

The strut R&R procedure has been shared before, so I’ll forego the perfunctory details –
https://mbworld.org/forums/c-class-w203/196922-diy-coilovers-tein.html

The hardware kit is required by MB for any strut installation. It consists of the requisite consumable washers, encapsulated nuts, and bolts with thread adhesive (Loctite) already applied. Is it absolutely necessary? Probably not. Keep in mind that these lowly fasteners are the only pieces holding the strut in place. They are inexpensive insurance against potential separation and the ensuing catastrophic circumstances...

Replacing the rubber buffer (bump stop) and debris shield is optional for OE applications. They are an inexpensive wear item, so their concurrent replacement would be appropriate. Please be aware that the typically stocked 203 320 09 44 is for the increased ride height US (code 486, non-sport) chassis. While they may work well for those encountering tire interference, it will limit otherwise reasonable jounce travel and contribute to understeer. Those of you running coilovers should disregard the MB part number(s) for this phase of the job..
The only challenge to facilitating the bearing replacement is safely compressing the spring. The appropriate tool can be rented or borrowed. My good friend is a Michelin dealer, so I'd arranged in advance to furnish lunch and beverages for his technicians. They had the bearings swapped out pronto! I implore you to always be mindful that compressed springs store a tremendous amount of potentially lethal energy. They will take your head off if it goes awry!


The car felt much more precise going down the road after the installation. It was an investment well spent in that its improvement was immediately apparent. Slowing the aging process and running with the young bucks...LOL!

rlee02135

great DIY John! but taking apart and re-installing the OEM strut is a HUGE pain...(without the right tools....like an expensive spring compressor)

TruTaing

Wow. I want that spring compressor. It would make life soo much easier than the ones you can buy from sears! (which i have :x)

How many miles did you have?

mig888

Excellent write up John - I'll be making use of this DIY sometime soon!

splinter

Thanks. You are correct though in that a commercial-grade strut spring compressor necessitates an ante of ~$700. They can be found at well-equipped rental yards for ~$25 a day. When the Michelin guy wants to borrow some of my carpentry tools, he doesn’t
have to ask twice.

Just clicked over 58k mostly easy miles. The faulty bushings had probably been in need of replacement for quite some time. They had long since exceeded their useful service life.

Let me know if you need a third hand with the install or any of your projects…I’d be pleased to help. To borrow a line from emrliquidlife; “I fear no bolt!”

mleskovar

Where/how do you check for wear?

drexappeal

John, it is really remarkable how much more vocal and active you've become on the forums. Very happy to see that after the many discussions we've had about your experience with working on cars over the years. Even though you were initially just trying to familiarize yourself with the w203 chassis, you've now proven that ultimately, it's still a car with many functions that have been around for a long time. Now, of course, the electricals are much more advanced than they used to, but so great to see this DIY. These are the technical threads that the w203 forum were missing for so long, but the DIY sticky continues to grow because of members such as yourself and quite a few others. Keep it up!

SeaCoupe

Nice Stuff Splinter!

Wondered where you had gone off to.

What was the origional sympton. Do you recall testing the play in my bushings. Will this rid me of that tease type slope?

E

trisonics

Wow! What a great write up. I took my car to a mechanic today and he said that it needs new struts. At that time I didn't know what it takes to change them, but now I am more knowledgeable. Thanks Splinter!

nlpamg

great post John! thanks for sharing it with us!

mckay

Nice write up.

My car is showing it age, and I have replaced the thrust/control arms already. I'm running Teins, and have noticed the steering does have a bit of play in it, so maybe its time to change this.

Have you thought about changing the wheel bearing yet? They seem to have a short life span, I've already replaced one side, time for the other.

splinter

Even though I’m about half deaf, the first indication was hearing yet another dreaded clunk from up front while traversing broken pavement. It was also having trouble producing consistent and repeatable alignment readings. The quick and easy test is to observe the upper strut mounts with the aid of an assistant. Have him or her crank the steering wheel from lock-to-lock while looking at the upper strut mounts from under the hood. Even with new bushings, they go through some weird machinations. Severely worn ones will allow the strut shaft to migrate almost throughout the entire perimeter of the tower opening.

While underway, they are subject to tremendous loads from the high castor angles that M-B incorporates into its suspensions. The W203 et al MacPherson-derived suspension is not an ideal setup. It is, ostensibly, relatively inexpensive to produce and assemble at the factory. To the best of my knowledge, M-B has no specification regarding acceptable wear limits. According to them, when they make noise, it’s time.

splinter

Thanks Drex! I’m truly flattered.
E, I’m not the one with a new lady in his life! I can always find a good excuse to get in the garage. When you and I last eyeballed the SeaCoupe, your bushings bushings looked okay. Didn’t think to look at the upper mounts.

How ‘bout you borrow the taxi for a weekend so you can compare?
Anytime. Thanks for the kind words.
Thanks Phil! When I can swing a M3/M5, I’ll post up more marginal tech on the appropriate forums.
Haven’t (yet) seen any signs of distress from the wheel bearings. I’m trying to get out of the upkeep rut so I can divert those funds toward go-fast parts! When did you replace yours?

C230 Sport Coup

I'd been wondering when a good time to post this might be.....

mad_vtak

Thanks for DIY

TC_L33t_Benz

Nice DIY.

cklass240

Does Anyone Have A Diy On How To Take The Front Shock And Spring Out? Anything With Pics And Exact Steps Would Be Great Im Trying To Put In My New Springs I Just Need The Diy For The Front 2004 C240 Thanks.

venemos

Try this link. It shows a coilover install on a C55.

http://www.mymbonline.com/forum/viewtopic.php?t=2755

cklass240

is the c55 the same kind of set up as a regular c class?

venemos

Yes, same suspension set up. (W203)

Shake

myMB

drexappeal

Did the DIY's in the AFTERMARKET/OEM MOD STICKY not help? Or did you just not look through there?

splinter

Torque specifications –

noreaga0221

Unbolt everything that looks like it holds the strut in. (disclaimer I've installed my own strut/spring combo)

tempr

I have to agree. I gives guys like me who don't have tools, working space or experience an insiders look. Now when my cars in the shop i refer back here so i dont get screwed by a mechanic telling me its an all day job or jerking on parts.