Gents,

Me sharing, for those who prioritize safety when jacking his/her car.

When I bought this car in 2018, one of the car built-in jack pad showed sign of dumb-azz jacking up the car with those cup shape jack saddle directly without any
protection or adapter, the jack saddle is something like below :

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2018 Archive




Cosmetic damage aside, such jack saddle is dangerous, if for the jack pad design of our W212 :
01. The jack saddle to car plastic jack pad can slip, as the total contact surface area is small and un-even.

02. The car plastic jack pad is strongest* at its inner rectangular cavity I marked green and not at the fat sides /shoulders.
*Strongest : A better description would be : least stress zone due to widest flat support area , also the cavity itself is kinda "self-locking" if proper MB jack adapter is in use.



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Our W212 is about 1,836kg ( 4,044 lbs ) for my model with 1/2 fuel and zero passenger/driver.
The front weight is 53.3% and the rear is 46.7%, weight distribution.
Let's simplified it to be all equal and at 2,000 KG ( 4,400 lbs ).
We use 500kg or 1,100 lbs per jack pad , accommodating bigger/heavier engine and more options on the car.




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If any person or techy uses those dumb-azz cup shaped jack saddle without any assisting intermediate material, the contact area is very small.
Below is in millimeters.



So damage is expected when and if jack saddle is of the crude shape.





The support cavity at the car's jack pad ( green zone ) is 1,639 square millimeters or 16.4 square centimeters or 2.54 square inch.

500kg / 16.4 = 30.48 kg per square centimeter
1,100 lbs / 2.54 = 433 lbs per square inch


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I spend many hours under my car using Quick Jack. So my life depends on my discipline for best safety practice and pre-caution when jacking up a car.
At the least, once a month or per 2 months I will jack up my car and inspect its under side, also after any long distance trip or Uncle Murphy bending my wheels.
I have faith using Quick Jack, but I keep my eyes always on the Quick Jack rubber pad, my MB jack adapter and how the seating inside the cavity of the MB jack pad.



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My jack adapter is made of PA6 ( nylon ) and I DIY it, using machine shop service.
You can buy ready to use ones : https://www.n54tuning.com/mercedes-b...er-by-bms.html


PA6 Nylon is so good and so strong , I love it. It can never snap or break into pieces, it will bend and get distorted...yes.
Its days of abuse.


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I realized my PA6 - Nylon MB jack adapter would need to be improved, as I want safer performance and the 4 jack pads on the car to stay pristine cosmetically,
because I will be ordering 4 new ones soon.

The current condition of the 4 jack pads at the moment.


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My humble jack adapter been so good, I decided to modify it today for better safety and protection to my now "abused" 4 jack pads of the car, which will be renewed early 2025.



The white base pad is also PA6 nylon , it is 20mm thick. The white base pad will take any abuse from a 4 point lift which has bad condition jack saddle.






Friction groove added on white PA6 - nylon base.





The size of the white PA6 nylon base is on purpose to be a tiny bit bigger than my Quick Jack provided rubber pads.






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Now, in emergency use, this upgraded MB jack adapter with flat and wide PA6 white nylon base, can readily take typical U shaped jack stand directly, as long the jack stand U support placed mid center.






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I also have ordered sort of heady duty CONDOM for the U shaped jack stand.


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I never anymore use this U shaped type jack stand. I am scared of it, because its supporting surface area is so small.


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The dimension of my PA-6 black nylon jack adapter : In millimeters.

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In USA, the MB jack pad is is so cheap..... US$11.35
https://www.mbpartsexpress.com/oem-p...p-plug-9986750

I got a quote of US$80 each from MB Indonesia !!!!
This is Guinness Book of Record for me, usually 300% of USA been the highest, example the AC refrigerant hoses.
Now this Jack Pad is $80 / $14.50 = 550% dugghhh. US$14.50 is the USA MSRP.

So I ordered genuine ones from Ebay, European sources.
Would be approx US$130.00 with shipping + import duty + VAT, for 4 pcs .....but 1-2 months arrival. I don't care if 1-2 months
US$320 vs US$130..... damn !!!! Its the mark-up percentage which hurts me, not the $$ per se.


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The improved jack pad adapter is good.

01. Improved load distribution to rubber pad




02. Safer and easier for hand when inserting the jack pad adapter to its "cavity lock" at body side jack pad.


03. The friction lines does work, now the improved jack pad adapter no more "slide" on the rubber pad.
This is specific to Quick Jack use, where Quick Jack is not a true vertical up lifting device, but a slide-back-lift up device.
Here is what I mean .........


1 is car at normal ride height, no jacking up at all.
2 is car at quick jack FULL jack up height.



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When tranny is in PARK, the rear wheel does not move....naturally.
While a Quick Jack is lifting up a car, it does it by sliding the car REAR-WARDS while lifting up too.
The rear suspension full droop is a lot, easy 20cm approx.

Left is full droop. Right side is RIDE HEIGHT.


So the rear tire due to being locked by PARK pawl, will not want to rotate while the Quick Jack Quick Jack is rising slowly.
The friction offered by the tire while still touching the floor, will cause the Jack Pad adapter to slide on the rubber pad while car load is still not maximum to the Jack Pad adapter.
When you guys buy and use Quick Jack, do keep this safety information in mind.

The sliding direction of Jack Pad adapter on the rubber pad is FORWARD, thus I used to place the Jack Pad adapter at the rear most position on the rubber pad, because
it will then slide forward up slowly as car rises and will stop sliding only when and if car load is already a lot at the Jack Pad adapter and friction is then high.

I marked my jack pad for easy orientation placement and the warning that the car will move backwards for 20CM ( actually 23CM ).





The position of the LOCK BAR ( with automatic locking CAM ) defines where the Quick Jack is supposed to be at, Left or Right side of the car.


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I wrote : The 20 cm rearward moving distance warning.



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