Should I change the transmission fluid on my car?

SOMEONE12132

MEMBER
2004 MERCEDES BENZ C240
2.6L
V6
2WD
AUTOMATIC
149,000 MILES

Recently, I bought a C240 with 149,000 miles and no valid service history. The only thing I have been informed of is when the oil was last changed. So far, I've changed the oil, air filters, and brakes. I have also inspected all the fluid levels, besides the transmission fluid levels.

I was wondering if I should change the transmission fluid on this car. I've heard mixed stories about changing the transmission fluid. I've also heard that these cars never need their transmission fluid changed as it's "lifetime", but I've also heard that they only last as long as the warranty of the car.

TLDR: Should I change the transmission fluid despite not knowing the service history of this vehicle?

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
48,363 POSTS

Yep, that is a tough one. I have heard it both ways as well. I don't think there is a correct answer for this one but if you want to service it, here is a generic guide to help you step by step with instructions in the diagrams below to show you how on your car:

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Check out the images (below). Please let us know what happens.

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