Long term results for 2001 V70 auto transmission drain and fill

[850 LPT]

How important is the 100 mile interval between drain and fills?

The reason I am asking is because I am doing this on my daughters 05' XC70 right now, realizing it's a different tranny as the one of the original post, but I did 2 drain and fills so far with 130 miles in between. We are driving this car to Denver at the end of next week and I would like to get 2 more in, but it will be challenging to get the miles in between.

Would 30 - 40 miles maybe be ok?

Some context. The car has 112k on it and the tranny looks like was never serviced, and it had an occasional hard downshift shift between 2nd and 1st, and also upshift from 1st to 2nd. That was pretty much resolved after the first drain and fill with Volvo fluid. The fluid was very dark but not horrible.

Thanks.

[BlackBart]

Is that so it thoroughly mixes old and new, or that the computer is adjusting to the slightly different transmission performance?

[dikidera]

Not sure who needs to read this or who might find this useful, but I have used a pump such as the one in the image to drain and fill oil to the precise requirement via the dip stick. Well mine was 200ml not 500cc but nevertheless.

The reason it works is because there is a rubber part on the bendable hose that makes a perfect airtight seal around the dipstick tube allowing the negative pressure in the pump to draw old oil in.

[volvolugnut]

I do not think there is a critical number of miles between drain and refills. I do think some miles of driving are needed to mix the old and new fluid. I think it is more important for the new, high detergent ATF to circulate and clean up deposits in the transmission. Then the next drain and fill will get more crud out of the transmission.
If you just drain and refill immediately, you may as well do the cooler hose ATF replacement process.
volvolugnut

[BlackBart]

I've been doing one D&F when I do the oil change. But we don't drive many miles per year.

[abscate]

It’s going to mix in 10 minutes of running, Dirk. Run it around the country for a bit then do another D&F

[BlackBart]

Getting it hot and using all the gears would be helpful I'm thinking.

[crasbe]

We did the first drain and refill on Friday on a transmission that has ~300k on it and had fluid changes before, but the ATF was quite dark already and it didn't always shift nicely. No codes or other issues though.

The old ATF:

Bild_2025-05-12_171751487.png (1.26 MiB) Viewed 244 times

We drained about 3.9L of ATF and filled it up with Ravenol ATF T-IV Fluid, as it was praised in a German Volvo forum to work as good as the original ATF if not better.
And in fact, the shifts got much smoother already. We'll do the next cycle soon and I'll report back.

[crasbe]

The car drove abour ~1600km now after the first drain and refill and we did the second round.
After the second drain, the fluid was still rather dark:

Bild_2025-06-01_220648181.png (746.35 KiB) Viewed 181 times

Bild_2025-06-01_220733658.png (806.9 KiB) Viewed 181 times

The gearbox ended up to be overfilled because I added 4L when ~3.8L came out (and that twice). Furthermore it had to be overfilled to begin with, because I sucked 800ml out and it was still a bit past the MAX line.

For the time being, it will stay a bit overfilled. We still have some oil for a third round, so I'll just fill in less next time.

The shifting did improve a bit more after the second drain&fill and we resetted the oil change mileage counter in the TCM. That did not really seem to have an influence, but we decided not to delete the adaptation values. It shifts nicely, so there is probably no need to.

All in all, the results are very good and I can recommend doing this method and the Ravenol T-IV ATF Fluid too. Of course we still have to see for long term results, but the gearbox now shifts nicer than it has the last years.

[dikidera]

I personally never saw an improvement ever from new fluid on two transmissions. Anyway, in order to get it cherry red, you need to do about 20 more quarts, and no I am not exaggerating this number.