Author Topic: To Shock or not to Shock  (Read 5332 times)

kampala

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To Shock or not to Shock
« on: December 30, 2012, 07:42:47 »
A bit long but I have found many differing views on Shocks so thought this might be of interest to others who are considering shock replacement.

The Problem
I have owned this car for a few months now and have sensed that the shocks needed to be replaced. The previous owner had replaced many front end parts including steering damper and ends …  but the front just did not feel as solid as I expect a Mercedes to feel.  Many on this forum have written that these cars feel very soft and that is normal and should not be compared to sports cars but to touring cars …  some have commented that significant nose dive is to be expected on these cars.

With all this in mind, I kept second guessing if the shocks really needed to be replaced and could not easily judge by the typical “push down on the car and watch for more than a bounce and a half.”

I decided to trust my gut and replace the shocks.

The Choice
Now the research began to decide on which brand – OEM Bilstens, Adjustable Konis, KYB, etc.  Much has been written and people clearly have opinions on what’s better or what they prefer … very confusing.   In addition I watched the Jim Villers video on springs and shocks and was very concerned about Bilsteins lifting the front end and I did not want to be changing or cutting springs. During the Euro Event this past September ( I did not have my car there) I asked Naj’s opinion and without hesitation he said go with Bilsteins.  Achim is all about correctness and absolutely concurred– gotta trust the gurus.

I had read that Bilsteins for non-pagoda Mercedes will fit the pagoda and these may be installed on some Pagodas contributing to the undesired extra soft feel.  Upon searching for Bilsteins it’s easy to understand the confusion as several auto parts suppliers sell non-pagoda Bilsteins as pagoda Bilsteins.   In addition, the part numbers have changed and the four green strips are no longer on the pagoda Bilsteins.  Once I confirmed the correct part numbers directly from Bilstein I ordered and installed the shocks on all four corners.   Bilstein Part numbers: Front - 24-005296 and Rear - 24-005395


The grunt work & a little surprise
The installation was pretty straightforward and as many have mentioned the difficult phase is compressing and holding the front shock compressed in order to install it.  Someone on this site had mentioned using a hose clamp around the rubber dust cover to hold the shock compressed and this proved to be excellent advice as it worked perfectly. 

The old shocks I removed were Bilsteins and were quite weak compared to the new ones …  easy to compress and decompress … the shocks were in need of replacing and I was glad I had made the decision to install new ones.  Out of curiosity, I cleaned off the lower portion of the shock and there I found the 4 green strips and to my surprise I found the date – July 1967.  These were the shocks the car came with from the factory as this 250sl was manufactured about September 1967.  I knew I bought a mostly original car from the original owner but 44 year old shocks were a bit over the top.  It is impressive that these shocks were still functioning without leaks.

Too tall or not too tall
Upon lowering the car off the jack stands I was quite concerned about the front sitting higher as mentioned by others … and it did sit a little higher upon first setting the car down but after driving it for less than a mile the car settled and sits as it did before … not higher in the front.

Needless to say the pagoda is much tighter, holds much flatter on corners and  holds flatter upon braking. 

I’ve attached a blurry photo of the date on the shock and a photo of the car after the new shocks installed … front does not seem any higher.

Happy New Year to all …

Oz
250sl - later - manual
280sl - 1971 - Auto - LSD

jmbour

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Re: To Shock or not to Shock
« Reply #1 on: December 30, 2012, 09:16:55 »
Hello !

I have the same problem : I presume that my 1971 280SL's shocks are original.

Where is your source for new Bilstein ? (France or US ?)
JMB

1971 280SL US
1973 280CE
1987 300 E
2005 C230

Flyair

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Re: To Shock or not to Shock
« Reply #2 on: December 30, 2012, 09:54:28 »
Great piece of first hand advice about something that we all, sooner or later, have to face. In my case, I am even more graceful, as I am to replace mines before the start of the new season, especially if I drive the car to the Euro event in Germany.

This post deserves to be linked up with our Tech Manual in my humble opinion.

By the way, I came across some write ups that some Bilsteins are oil based while the others are filled with gas. Which ones are recommendable? I gather that the original ones are with oil, but in terms of security I think thic should not matter, as I am not driving a concours car.... :)
Stan
1971 280SL
2011 SL550 AMG
2011 GL
2015 GLA

Iconic

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Re: To Shock or not to Shock
« Reply #3 on: December 30, 2012, 14:09:18 »
My experience was very similar to kampala's with the only significant difference being that it took approximately 50 or 100 miles for my front end to settle down to its current height.
1970 280 SL Automatic, USA version, Grey-Blue (906G/906G), Blue leather (245)
1968 SS396 Camaro Convertible (owned since 1977 -- my first car :D)
1984 Porsche Euro Carrera coupe, LSD, SlateBlueMet/Blue
1998 BMW M-Rdstr Estoril Blue
1970 280 SL Automatic, Anthracite Grey-173G, Red Interior-132 - sold

Flyair

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Re: To Shock or not to Shock
« Reply #4 on: December 30, 2012, 17:15:16 »
Iconic,
I think that settling to the right hight depends on the driver's physical features… in clear how much his weight is able to help Earth's gravity to do its work ;)
Stan
1971 280SL
2011 SL550 AMG
2011 GL
2015 GLA

ja17

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Re: To Shock or not to Shock
« Reply #5 on: December 30, 2012, 17:38:15 »
The Pagodas originally came with gas/hydraulic Bilstieen shocks.  They do provide a small amount of  lift at each  corner, even the original shocks. As with conventional shocks, the oil provides the dampening.  The nitrogen gas , besides providing some up-force, is under pressure and prevents the oil from "foaming" and loosing dampening force under rapid dampening. 

The "heavy duty" version were used on the cars equipped with AC because of the extra weight of all the AC parts. You can test your old Bilstiens by turning them upside down  and compressing them. The amount of dead travel at the top is the indication of how much nitrogen has escaped from the shock over the years. If you have one that the rod wiill not extend on its own , all the nitrogen is gone.
Joe Alexander
Blacklick, Ohio
1969 Dark Olive 280SL
2002 ML55 AMG (tow vehicle)
2002 SLK32 AMG (350 hp)
1982 300TD Wagon turbo 4spd.
1963 404 Mercedes Unimog (Swedish Army)
1989 flu419 Mercedes Unimog (US Army)
1998 E430
1974 450SLC Rally
1965 220SE Finback

kampala

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Re: To Shock or not to Shock
« Reply #6 on: December 31, 2012, 06:37:57 »
JMBOUR - I purchased these from eshocks.com as they were an authorized Bilstein distributor and also one of the very few that listed the part number correctly.  They are located in Michigan USA but do ship internationally. Since my Car lives in California it worked out well as I am in USA at the moment (will return to Paris in a few days -- very close to you --- I'm in the Champs de Mars area.) If you want a helping hand when you replace yours, let me know.

FLYAIR - the new shocks are described by Bilstein as being "gas pressure shocks" ... no choice when going with Bilstein ... they make one model specifically for the Pagoda.

Best

Oz
250sl - later - manual
280sl - 1971 - Auto - LSD

jmbour

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Re: To Shock or not to Shock
« Reply #7 on: December 31, 2012, 10:59:03 »
Kampala,

Thanks for your offer. I will try to find some in Europe with the reference numbers (I presume the classic center could provide them, but at what price !)
My car is in the Périgord region where I spend half of my time (the other half in Paris XVéme Vaugirard).
I am now working on the dashboard (clock repaired by JDO in the UK, replacement of heater control levers, and speedometer cable).
I will also have to fix the rattles of the left window before thinking about the shocks.
But it is very important to find the most original parts, as all shocks are not equal.
I replaced the original Boge on my W114 280 CE by "modern" low cost gas Gabriel shocks : it was awful, these shocks are so hard, and the car was so uncomfortable on normal roads that I preferred to but back the old ones.
JMB

1971 280SL US
1973 280CE
1987 300 E
2005 C230