When should transmission fluid be changed

We gets the oil question about every other day, but we never really hear about transmission fluid changes.

With talks about machine filings being in the engine, couldn’t the same thing be said about the transmission? Would changing the tranny fluid at the same time as that first oil change be a good idea?

I don’t think the first oil/filter change is because of metal filings…usually a break-in fluid, unless I am mistaken…which is possible…
for the transmission usually one follows the scheduled maintenance for the vehicle…many suggest changing fluid and filter between 30 and 50,000 miles and never flush. more opinions will follow this post…

Don’t many transmissions have a magnet to catch small metal particles that could cause excessive wear?

No. Not every oil change.

But at the 30,000 mark, pull the pan and check out how the tranny’s doing. Reinstall the pan and do a fluid EXCHANGE. At the 60,000 mark, don’t pull the pan just do the exchange. At the 90,000 mark pull the pan…

Treat your automatic transmission like you do your engine. It usually costs more to replace a transmission than it does an engine. Especially now that they’re electronically controlled.


Pan drop, fluid and filter change every 25-30k miles regardless of what the owners manual says. Refill using OEM fluid.


I like to change the fluid somewhere between 30-50k. I do a fluid exchange (don’t confused this with “flush” as to imply solvents/chemicals) via the cooler lines. I drop the pan too, but it’s easier with an almost empty pan. After the initial cleaning out of the pan, that should be good enough just about forever.

You only change a fraction of the fluid in most transmissions with a pan drop. Even if you wanted to do partial changes for preventing some “shock” nonsense, it’s easier and tidier to do it via the cooling lines.

I didn’t say every oil change, just that first one. The one that’s always made into a topic on here.

I see a difference of opinion on this board about the benefits of doing a “pan drop, filter & fluid” change alone vs that plus a fluid exchange.

I know a pan drop leaves the old fluid in the converter. If that were any concern, why aren’t fluid exchanges recommended by the car makers?

My question is:
If someone does a “pan drop, fluid & filter” change every 30K miles, would they ever see longer transmission life if they additionally did a fluid exchange at those 30K intervals as well?

I’m of the opinion that the “pan drop, fluid & filter” change every 30K miles will lead to long satisfactory transmission life. What added benefit to transmission life will an exchange add?

First check the owner’s manual. That is the minimum. After that, follow Transmmans advice. You can do less, but it is likely to cost more in the long run.

You will hear the argument that you should never change the fluid because so many people change the fluid only to have the transmission fail shortly later. Remember that they only did that change because they were already having problems (likely went 125,000 miles without a change) and did the change in hope it would fix the damage already done. Of course it will not.



Thanks for that pointer. Unfortunately that link promotes flushing in the context of highlighting Wynn’s Transerve II+ flush equipment. That kind of promotion makes the recommendation more biased than I was looking for.

Maybe I should simplify my question and rephrase to:
Is there any evidence that only doing a “pan drop, filter & fluid” change every 30K isn’t enough?

I agree with Joe; regular 30,000 mile fluid and filter change will make the transmission last the life of the car. I have been doing this since my first automatic in 1965, and only spent $185 on actual transmision repairs since that time.

The flush in between is unnecessary, but dealers and fast lube places love it as a quick profit maker.

You gotta be kidding me?

You mean to tell me that if you read something for checking the fuel pressure on a 2001 Infinity QX4, and are instructed to use an OTC J-44321 fuel pressure adapter tool that the article is highlighting OTC Tool Company and is being biased, so it should be disreguarded?

Your logic makes no sense!


That page is hosted from cars.com. Cars.com is a commercial site. They look for advertisers and they have a number of “content partners” for their material. I don’t know if Wynn’s products and cars.com have any mutually interests.

However, the above is largely irrelevant, because I was looking for personal input from the many who contribute on this forum.

i thought those pan magnets were gimmicks that snake oil salesmen sold