Hi everyone,

I have a 2018 C300, and I’ve been reading different things about the transmission service and it’s in some 60 K and others say 77K.

I am overdue, and I completely overlooked this by mistake, I am now at 80 K miles and the transmission is working fine.

The only issue I have is the same thing that I see a lot of people experiencing is the harsh down shift from 2-1st gear And only occurs when I am driving in manual mode with the paddle shifters.

I’ve heard mixed things about doing the service late, so I wanted to get everyone’s input, I’m going to be taking the car into the dealership to get the service done.

I hope that it’s not way too late to the point where I’ve damaged the transmission.

thank you for your responses and advice!

 

Yes, it’s specified by the manufacturer.

 

Yes that is overdue quite a bit but you might be fine, inspect the old fluid when you are done the fluid change you could probably send it to companies like Blackstone labs if you are worried.

 

You are fine, what would the other option be, not doing it at all? Better late than never. The dealer is usually reasonable on this job but an indy that know what to do would be even better.

 

I would change it. It's better to do it latter than never. I know there are those who belive in lifetime transmission fluid but i think those people are mainly the engineers at MB and thats about it.

 

Yes, there once was a MB transmission that MB said it is a lifetime fluid thing but I think it backfired. Forgot which transmission it was.

 

I have a 2019 C300 with 54,300 miles. Standard MB service has something called a 60,000mile/6Year service. It includes full transmission service, all filters changed, brake fluid, and a few more "checks" than other services. There is a "required" list and additional things on the "recommended" list for this. I had the 60K required service done at the dealer costed around $1700 - quite a bit.

However, I have the extended warrenty in place (from MB) until Dec 2025 and I want to stay in compliance. In June (3 months ago), I had a "check engine" light which led to an "Oil Pump Valve" repair. It would have cost about $3,100, but was fully covered by the MB extended warrenty. For this 60K service they unnecessaily changed the oil again after only 3 months - I missed it - and I was not happy at all - an extra $250 or so.

The next few services - 70K, 80K, and 90K - will all be much less at the dealer than the 50K and 60K mile services - they will all be regular A or B services.. Starting now, I will use Indy shops for inpection (PA state) and resulting needed fixes (tires, brakes, rotors, suspension, ...), and use the dealer for the annual service after the inspection. - Because - There could be a successful class actions about the 4 cylinder engines resulting in a recall. (There is a recall underway in California, and a number of other 4-cylinder engine failures reported in the the W205 blog and other MBworld blogs. Some of thes services were $9-10K out of pocket.) Such a recall might require MB "extended warranty contract" specified service which the dealer would have clearly provided and which MB might contest from an Indy. The few extra hundreds of dollars would clearly be worth it if this occurs.