When to change CVT fluid?



Glad you like yours. I don’t think they have the programming right yet. They sure don’t get the mileage they are rated for.


My vote is to change at 25K, as per severe service schedule

I service all transmissions as per the sever service schedule, both at work, and on my personal vehicles


I get well over rated, 30-32 MPH on the highway in the summer. 28 or less in the winter. Interesting to be running under cruise control at 70 MPH and watching the RPMs change as you go up or down a hill.

I wonder, since the dealer recommends no fluid change, if anyone at the dealer has experience in doing this difficult change? I assume someone had some training, but actual experience is importance. That is another factor in decision as to when to have this done.


Thats pretty easy driving , 8000 a year ? Thats about 1/2 the average . Just go with the manual . A lot of trannys nowadays dont even come with a dipstick and the dealer needs to do it . Unless CVT’s are on a totally different factory schedule most trannys can go 100000 before doing the fluid and filter .


Your statement is very different from the others… My present tendency is for 50k, but I vacillate.


What year is your Forester?

I’m not yet convinced that simply servicing the fluid is a difficult procedure


Where are you coming from . . . ?!

I agree that a lot of transmissions nowadays don’t come with a dipstick

But how do you then conclude that only a dealer can service the transmission?!

But what if it were 8000 miles of city driving/year . . . ?!



it’s mostly highway driving.

As I said, I suspect the dealer has zero experience with changing the fluid. But I’ll go poke around next time I’m there.


On the surface, replacing the CVT ATF should be easy. It is similar to changing the fluid in a manual transmission. There is a drain plug, a fill plug and another plug that you use to determine the level. You drain from the first, replace it, then pull 2 and 3 and fill 2 until fluid comes out 3. You start the engine after the first couple of quarts are added, then start the engine and fill till fluid comes out 3. The sticky issue is that you need a diagnostic tool that reads the ATF temp and you set the level at that temp. That temp is between ambient and normal operating temp.

This applies to the Subaru CVT.


My questions and statements to Bill Russell and vipergg weren’t meant to imply lack of knowledge

I’ve serviced many different types of transmissions . . . including cvts . . . on various brands of vehicles


Perhaps but it’s not much different than filling a new transmission after replacement. Most of the techs in our shop have experience with replacing transmissions, one tech replaces 2 to 3 each week for a recall repair on hybrid vehicles.


But this is a CVT… but perhaps I’m overthinking this…


you might be overthinking the whole thing, as you mentioned

and I personally have a hard time believing that none of the mechanics at the dealership have experiencing performing fluid services on the cvts . . . there must have been some customers who went for upsells, based on mileage, by now

Servicing cvt fluid is generally easier than servicing transmission fluid on a newer conventional automatic transmission with no dipstick . . . for instance Benz, Ford, Toyota, and so on

I’m not really familiar with Subarus, and there might be something about the drivetrain layout which makes servicing the cvt fluid unusual, but I can’t imagine it’s that difficult


In my half-century of driving, I’ve never changed any fluids other than oil, and it’s never mattered one whit as far as I can tell. I fully expect it to continue to not matter.


Yeah I’ve got a half century too and a million and a half miles in that period. It was one thing to be able to have a 350 trans rebuilt for $1500 but quite another on the high cost 6 plus speed and CVT transmissions. The consequences of poor maintenance are quite a bit higher. Therefore I say 30,000 and will be very careful to not buy a used car that has been neglected.


When I took it in for the 30k mile check, I asked them to check the CVT, the perfect opportunity to sell me on a fluid change, but said they checked it and it was OK, whatever that means. But, yes, they must have changed a few by now.


CVT transmissions have less moving parts and CVT fluid holds up longer. I wouldn’t do prior to 50K.


Why does CVT fluid hold up longer? I’m not disagreeing with you, just trying to learn something.


I’m guessing less moving parts less heat and breakdown of CVT fluid, I just got off the phone with the dealership about this for my Suzuki SX4, they told me change every 120,000 miles. Each vehicle is different.


watch your user manual they all different but in general it is good to replace it every 20k-30k miles(including filters) - which dealers do not do…