2004 CLK500 *ALL* Fluids Replacement
1-Brake Fluid replacement with brake bleeder tool or pump/pump and bleed method. Is it appropriate and fine?
2-Power steering fluid, how can I do it?
3-Radiator coolant replacement, how can I do it?
4- Automatic transmission fluid, planning to drop the pan, replace the filter and add 4-5 quarts of Shell ATF. Any tips?
5-Engine oil(Mob-1) has been in the car for 1 year, but have less than 3,000 miles, should I replace it?
6-Air filter, how often they should be replaced and where can I get them cheap?
Any helpful video, thread or advice would be greatly appreciated.
Thanks in advance for the help
5-Engine oil(Mob-1) has been in the car for 1 year, but have less than 3,000 miles, should I replace it?
6-Air filter, how often they should be replaced and where can I get them cheap?
5- You also need a filter here and oil should be changed every 13,000 miles or 1 year whichever comes first so yes go ahead and change it.
6- I bought air filters online before. www.rmeuropean.com or Amazon.
2) Not sure how you drain it (my hose burst). To bleed have the front end up on jack stands, pour new fluid into the reservoir, turn steering wheel from lock to lock to bleed the air and keep adding fluid.
3) I am doing this now, there is a drain on the bottom corner of the radiator. To get the fluid in the block you need to undo the drain plug near the back. I didn't do this. I changed the fluid via radiator only back to back 3 times with distilled water and I will do the final replacement with mercedes coolant in a few days. This gets 7.5/11.5L out each time. If you do it 4 times you get 98.6% of the old fluid out without having to even get a jack let along crawl under the car and risk having the block bolt not seal properly.
4) I did this recently, I imagine a lot of your questions might be answered in the thread I made. Order genuine pan gasket, drain bolt/washer, fluid, lock pin and its not a bad idea to replace the electrohydraulic bush if you are game for it.
5) I always wait for the mileage rather than time but that's just me. I wouldn't but it certainly won't hurt.
6) Genuine mercedes are not that expensive. Parts.com and a bunch of other sites have some of these items cheaper than the dealer.
Transmission fluid https://mbworld.org/forums/clk-class...ion-flush.html
My power steering episode https://mbworld.org/forums/clk-class...ering-yay.html
1- Yeah, I am going to use classic brake bleeding technique to replace the fluid. I have this brake fluid "81220142156 Brake Fluid; DOT 4 LV Low Viscosity; 1 Liter"
2- Can I just siphon off PS fluid and add new while moving steering wheel end to end? I have this fluid " CHF11S Power Steering Fluid; 11.S Synthetic; 1 Liter"
3- That's a really good tip and smart advice, just crack the drain bolt and wait for the coolant to drain? Not sure if my car has a drain bolt or no? Can you please share a pict of it? 4-5 gallons of distilled water should be enough, correct?
4-I have filter, gasket and fluid. Not planning to replace lock pin, screws and drain bolt/washer. Should I replace all whatever you did?
5-Going to replace oil and filter
6-Do I need to two air filters and are they easy to replace?
1-Brake Fluid replacement with brake bleeder tool or pump/pump and bleed method. Is it appropriate and fine?
2-Power steering fluid, how can I do it?
3-Radiator coolant replacement, how can I do it?
4- Automatic transmission fluid, planning to drop the pan, replace the filter and add 4-5 quarts of Shell ATF. Any tips?
5-Engine oil(Mob-1) has been in the car for 1 year, but have less than 3,000 miles, should I replace it?
6-Air filter, how often they should be replaced and where can I get them cheap?
Any helpful video, thread or advice would be greatly appreciated.
Thanks in advance for the help
1 - Any method of bleeding is fine. The pump the brake method works fine. Just get good brake fluid.
3 - Crack the drain plug let it drain. You can flush with water a few times if you want but if the coolant is not old/dirty I see no reason to complicate things.
4 - Make sure you have the correct transmission fluid. In order to do a flush you'll need more than the transmission can hold. Drop the pan, replace fileter and gasket. Add whatever fluid you lost.
To do a full flush: Disconnect the transmission cooler line at the radiator, start the car, let the transmission pump out 1-2L of fluid at a time, turn car off, add new fluid (whatever you removed). Repeat until fluid is clean/red.
5 - Replace the oil. It's not that expensive.
6 - Depends on the filter. Take a look at them. Are they dirty? Then replace.
7 - Differential fluid? That's also a fluid in the car
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There is a flat round plastic "tap" on the bottom of the radiator left side of the car. Turn it and coolant will come out a small pipe just above which points backwards. I slipped a small hose over it and directed it into a pan. You need to remove the plastic under cover to access it. If you have clean clear blue Mercedes coolant i would do 2 drain/fill cycles only which gets over 80% of it changed with minimal effort. Mine was green non-oem anti-freeze hence i am doing 4 drain/fills. This method also also has the advantage of mixing with the heater circuit coolant while you drive with the heater on in between changes. It's summer here so great time to have the heater blasting. You get 7.5 liters each time which is approximately the same in qts so 3-4 gallons and 3 liters of blue concentrate will suffice.
You have to break the lock pin to fill the transmission so i would get a new one. They are approx $1 same with the drain bolt and washer which are one use only. You can either to a full flush as outlined above which is best. Or you can just drain the fluid, replace filter and refill. This changes about 45% of the fluid. It is much easier and if you do it regularly you will have a healthy transmission. You will need to buy a dipstick to measure the fluid level.
Oil is approximately $150 here which is the only reason i wait longer to do oil changes. Mobil 1 is very cheap overseas so go for it. Air filters are easy to change.
I am still using the original pan and drain plug.
I am still using the original pan and drain plug.
TW2, can you please share a pict of the radiator drain bolt, please?
There is a flat round plastic "tap" on the bottom of the radiator left side of the car. Turn it and coolant will come out a small pipe just above which points backwards. I slipped a small hose over it and directed it into a pan. You need to remove the plastic under cover to access it. If you have clean clear blue Mercedes coolant i would do 2 drain/fill cycles only which gets over 80% of it changed with minimal effort. Mine was green non-oem anti-freeze hence i am doing 4 drain/fills. This method also also has the advantage of mixing with the heater circuit coolant while you drive with the heater on in between changes. It's summer here so great time to have the heater blasting. You get 7.5 liters each time which is approximately the same in qts so 3-4 gallons and 3 liters of blue concentrate will suffice.
You have to break the lock pin to fill the transmission so i would get a new one. They are approx $1 same with the drain bolt and washer which are one use only. You can either to a full flush as outlined above which is best. Or you can just drain the fluid, replace filter and refill. This changes about 45% of the fluid. It is much easier and if you do it regularly you will have a healthy transmission. You will need to buy a dipstick to measure the fluid level.
Oil is approximately $150 here which is the only reason i wait longer to do oil changes. Mobil 1 is very cheap overseas so go for it. Air filters are easy to change.
Is full flush better than dropping the pan or it's an overkill?

A full flush involves taking the return hose off that goes back to the transmission and starting the car until fluid comes out, turn car off, fill up with more transmission fluid and repeat until all the old stuff has cycled out.. OR flushing with a fluid swap machine which does the same thing. These methods are better than just swapping the fluid in the pan since you are replacing all of it not just 40-50% of it.
I did a pan drop and only changed that fluid approx 3.6 liters in my case because it is extremely easy, doesn't require any particular skill or equipment and I rather do that every 20,000km than pay the $900 they want for the full flush at the dealer. Next time I will only change the fluid, I will not drop the pan and change the filter again. I possibly I will do this every 2nd or 3rd time instead.
This is just my opinion, you must do what you are comfortable with so please feel free to ignore it but- I see no reason not to take the drain bolt out of the transmission pan to drain it. It is not torqued in that tightly (20Nm), the replacement one is literally $2-3 from the dealer and unless you have a car lift and awesome skill I promise you will make a huge mess if you try and remove a full pan. Clean the area, it comes with a new washer anyway and it will definitely seal perfectly.

I am going to do a pan flush, better than nothing. Going to check with the dealer for locking pin and drain bolt/washer.
Thanks again for your help
One thing I learned from him is you have to keep everything absolutely clean when working with the transmission. He cleans the pan inside out every time.

remove fill / check plug on left side of diff.
remove drain pug on bottom of diff, drain gear lube.
it takes 52oz. +- an oz. to fill in a normal open diff, limited slip ymmv.
I use Mobil 1 Synthetic Gear Lube 75w-90 LS (limited slip) as I have a lot of this around for my race cars. There are several friction modifiers additives you can add for longer life if you want. I have my wifes 04 CLK500 on a 100,000 mile change schedule for the diff.

if yours was never changed, i would do so asap. better to get the metal and gear oil out.
also to the original op, i have found that the best trans pan gasket is Woco, the supplier to mb, and i always use the mb filter, i get them @ rm.
i have flushed the trans 4 times so far, i have converted from using the pan bolts replacing them with studs and nuts.
One thing I learned from him is you have to keep everything absolutely clean when working with the transmission. He cleans the pan inside out every time.

Do you need a pump and hose? I have not done mine either. Another supposedly sealed for life component.


whenever we purchase a vehicle, one of the 1st things i do is put it up on my lift, and make a maint schedule.
my favorite CLK misconceptions are:
filled for life fluids, lifetime vehicle wheel alignment, they cannot be aligned, they are hard on tires, they are hard to work on, as good as MB approved fluids.
if you hear any of these lines, be skeptical of the info you are getting.
we purchased the wifes 04 CLK500 used because she puts so many miles on. overall it is a very dependable car when properly maintained. the way she drives on a lowered CLK, she gets over 60,000 miles on a set of tires, and on 1 set she had 76,000 miles.







