VenomX

Hi. I have a W203 C240 2002 with the 722.6 ( 5 speed gearbox )
Only has 33K miles on it, so very low.

Confusion as to whether changing the ATF ever needs doing or not ? On "https://lite.servicemercedes.co.uk/ess/pc/ " IF I enter my car details it says to replace ATF at 37.5K Miles for VIN R1xxx and above. However my VIN is R0xxx. So it appears Mercedes say it does not need to be done on my specific car.

My car has an ATF filler cap under the bonnet, but it isn't the style which has a red clip in it, just a black filler cap and nothing else.
It looks like this,

slammer111

You have the standard 722.6 transmission. The cap tab is probably just dirty. If it's not red, it was probably replaced by someone else at some point. I don't think MB ever made any non red tabs.

No transmission fluid will last a lifetime. Even if the fluid isn't cooked, the chemicals will eventually break down. Also, the filter will eventually clog from all the bits of clutch material.

Originally MB said the transmissions were sealed for life, but then backtracked to 60k km intervals.

As the fluid is synthetic, personally I'm more of the belief that distance is a much better metric than time when it comes to fluid life. There are so many variables (driving style etc.) that the actual fluid life for a given car can probably vary quite a bit. I imagine the MB recommended interval was selected for warranty/liability reasons.

As for your car, it's still below the recommended 60k km. No need to change the fluid unless the transmission has been abused.

VenomX

Still at low mileage so I am considering doing an interim service on the ATF.
I am not confident getting under the car and taking the trays off and draining through the sump itself.

However, I do have a very good vacuum pump which I used to do the engine oil successfully. Can I do the same with the ATF through the dipstick tube ? ( location shown in the original post )
I have heard of people doing it this way on Mercedes. I know it is not as effective as draining from the sump, but I am thinking at least changing as much as I can through a vacuum would be good enough for now

Would be buying Fuchs 4134.
The gearbox is currently 100% smooth with no issues at all


Thanks

C230 Sport Coup

If it aint broke, don't fix it.
I went 120K miles before my transmission seriously rebelled.
At the time they were saying "sealed for life" so I was quite upset thinking I needed a
new tranny. I did a full flush and it was like new again. Now at 258K miles and the tranny gives me
no trouble, unlike other things LOL with a car of that age and use.
With only 33K miles, and running good, I wouldn't touch it untill at least 40K.
It's a PIA job without a lift. And I don't think you can just suck the fluid out and
replace. You need to replace the filter as well, AND if you've never inspected the connector
where the tranny connects electrically to the rest of the car, thats the thing you gotta worry about.
The original orings would leak, and fluid wicks up into computer, and makes a mess, hard to get the
oil out of the wiring loom. So, you also need to replace the plastic piece that holds the cable and houses
the Orings. They've changed them numerous times over the years. Do that along with the trans service.
How long have you had the car? If you've never inspected the cam sensor wires, you need to.
They updated with pigtails to keep oil from getting into the wiring, and also you need to make sure you
don't have a Valeo radiator. I will kill your tranny. Thread on all this stuff if you look hard enough.
And so much more info these days than back in the on Youtube.