Just to be sure we are on the same page. You changed the fluid and filter, and the transmission is no longer slipping?
However, now the fans are roaring?
If this is the case, we need to make sure it is the fans and that they do this even after the engine is hot.
It is common for the fans to be loud when the engine is cold. So, I would suggest you take it for about a 20-mile test drive and see if the transmission is shifting properly and if the fans quiet down.
It is unlikely that this is related to the transmission issue but let's get a little more clarify on the issue and go from there.
If the fans don't quiet down, then I suspect we have an issue with the temperature sensor to keep the fans on high but let's get there after this is clarified.
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Wednesday, December 1st, 2021 AT 6:39 PM