no you don't but really please suggest other reading not to without at least you fully understanding the purpose of a full fluid flush and replacement and the 2 main and really only reasons why not to! You are not by your own words a very capable or knowledgeable DIY. So why are you giving bad advise? LOL
Dude it does not cause issue unless 2 things... it was done incorrectly and without a professional transmission service machine
OR

The transmission was so badly damaged that the clutch plate friction material is floating in the fluid and is the only thing that is allowing the clutch pack to partially engage the clutches. Draining and changing the fluid or flushing the complete fluid in the transmission and replacing it also removes the only thing keep the transmission to engage a gear and shift somewhat. but that badly damage transmission was soon to fail anyway.

 

Yeah, I think a simple drain n refill replaces not even half the fluid that significantly improves lubrication but don't have to worry about significant friction loss on the clutches.

 

Those works only if the transmission is not already failing.

The dilution factor often used works so what if the first oil pan filter and oil service is done and then followed up about every 1500-3000 miles max with a drain and fill and then a repeat oof pan filter and fluid change at no more then 7-10k miles from the first pan filter and fluid service.


The wording improves lubrication is not accurate change that thought and discription to helps improve cleaning the transmission internal parts and then you would be accurate. ATF is basically a very high detergent oil . Old school DIY and many mechanics of the Dino oil era use to drain engine oil refill with ATF drive several miles some a couple of day to super clean the the lower short block and head and valley area before drying and changing the oil and oil filter.
That practice is not done much any more because synthetic oil are high detergent formulated .

 

I have never run a full synthetic oil in my 33 year old truck, 191K miles. I have been running blends but I'm pretty certain that is still largely conventional oil. I was going to switch to full synthetic beginning next month. I'll be interested in seeing what kind of sludge comes out of that thing the next time I change it.

 

The “sludge” as you call it may not be seen by draining. But when the oil stops dripping during the drain take a can of WD40 with the red adjustment nozzle spray tube and spray directly into the drain plug hole and the watch what drains out. You may need to go through a few can of WD40 before it starts to come out only WD40.

Just be clear WD40 in no way any remains in the oil pan or sprayed on and part of the reciprocating assembly will harm any part. The new oil will dilute the remaining WD40. Also while so many think WD40 is a lubricant it is actually primarily a solvent .


I never post anything I don’t do or have personal tested or tried.
And yes you can find examples on this forum.

 

I changed my Differential, transfercase ( PTO) and transmission oil every 40,000kms on my CX-5.

 

What does the WD40 stand for? Water Displacement...not sure about the 40.

 

Yeah, so about 30K miles. I'm there!

I have hand pumps but I hate them. Gonna get a pneumatic pumper/extractor. I'll use it for tranny as well..

 

It was the 40th formula (or version) that they made when trying to produce their product.

 

I see a simple question got a few of us running to the internet to learn. I didn't know what the WD stood for. Never thought to care to learn. Now I know. LOL
I do know that I stopped using it decades ago as anything other than to remove stickers and as a solvent .
I do use it as one ingredient when I make my own break in oils and grease for various Engine and manual transmission or gear boxes like differentials projects that will have new parts or components and have motor or gear oil for the break in period .