I’ve been driving for years and never had expensive fluid system flushes recommended until recently. On my 2002 Honda Accord with 40000 miles I spent hundreds on a brake and transmission fluid flush. Today, on my 2003 Acura TL with 66,000 miles, I spent more hundreds for a power steering and brake system flush. Is this service really necessary?

Tranny Flush - A POWER flush isn’t needed, but a drain and refill is.

Brake Fluid Flush - Yes. Brake fluid absorbs water. Need to remove the water with a flush.

Power Steering Fluid Flush - NOT NEEDED

Agree; most of these flushes are only needed to pay for the expensive flushing machines these shops have. They are high profit services which most of the time do not need and in many cases (such as transmission) do more harm than good.

My standing orders to my wife are: if you hear the word “flush” mentioned, say “no” and call me right away.


Could you and Tester discuss this and come to an agreement? The video he posted doesn’t agree with you. Sure, it’s an advertisement, but it was recommended by someone we’ve come to trust. I’m skeptical about the 24,000 mile interval, especially since my cars don’t have it in their service interval until 100,000 miles. But the part about draining only 30% of the fluid by gravity is compelling. Even if it is twice that level.

I’m skeptical about the 24,000 mile interval, especially since my cars don’t have it in their service interval until 100,000 miles. But the part about draining only 30% of the fluid by gravity is compelling. Even if it is twice that level.

Assuming you only change 30% (I low figure IMO) in a transmission fluid change, doing it every 24,000 miles should mean you average contamination level is going to be less and the average age of the fluid in the transmission is going to be newer than someone who managed to change 100% at 100,000 miles and I would suggest (I really should do the numbers) that the same would still be true at 200,000 miles. If you want to carry it out to 300,000 miles the average over those 300,000 miles is likely to still be better.

Not only will the average age and condition of the fluid be better, but the gunk removed when you cleaned out the filter area, will be an additional benefit.

I guess I should add that I had assumed that the flush would be a 100% change, but that is not likely. As it is flushed the old and new fluid will co-mingle giving you not all new fluid, but rather a mix of old and new.

The video is highly misleading; the 24,000 mile interval is too short, especially if “all the fluid” is replaced. I’ll bet that at 24,000 miles of normal driving that fluid which our guy says needs to be flushed is still bright pink.

The idea that only 30% of fluid is replaced with a pan drop is also misleading, the % is much higher.

Since there are car makers who do not even have a fluid change in their recommended schedule (for normal driving) you may conclude that a conservatively driven car, not overloaded, in a moderate climate will go a very long time before causing any transmission damage.

If the smooth talking guy really had you interest at heart, he might recommend a flush every 30,000 miles followed by a flush AND a pan drop cleanout at 60,000 miles.

This “honest” guy also does not breathe the word “FILTER”, he just ignores it. The filter will eventually clog up and cause transmission failure.

For trailer towing, if you read most manuals, the fluid/filter change is about every 15,000-30,000 miles since it causes a lot of wear.

The last time I had my car in after trailer towing, the tech slowed me the stuff in the pan, and yes, that was stuff you could not flush out.

My Toyota has a recommended 6 years or 60,000 miles and for my Nissan it’s only recommended to change the fluid at 30,000 miles or 2 years when towing a trailer, having a large car top carrier or driving on dusty & muddy roads. I change it anyway every 40,000 miles. NOT A WORD IN EITHER MANUAL ABOUT FLUSHES!!!

Since I am only an engineer and not an experienced transmission technician, I would like “transman” to comment on these commercials.

I have had automatic cars since 1965, and have installed 7 trailer hitches and transmission coolers over that time. Doing the normal pan drop and filter chnages has served me well. We have only spent $185 on transmission REPAIRS since in that time (44 years).

There is a doctor in my area who recommends regular enamas, claiming mother nature can’t quite clean you out the natural way. He runs a highly profitable operation “cleaning people out” (in more than one way). From the beginning of life on earth people have (with rare exception)gotten rid of things the natural way, thank you.



Thanks for this second source of information. It’s too interesting to bookmark, though. I copied it to a Word document and saved it. I was skeptical of the Rusty Wallace video. It seems too much like a commercial for lotsa tranny flushes. Sell more, make more; sell more, make more! But transman had similar thoughts elsewhere, and I appreciate what you and he have to say on the subject.

I have a great deal of respect for tester and most of his answers, but when it comes to flushes, I strongly disagree with him. Brakes and toilets get flushed, nothing else, especially transmissions.

As for the Honda and Acura, only 2.5 quarts can be drained of the 6 quart capacity and it should be done every 30,000 miles. There is no pan to drop and the filter is not replaceable. Even the factory service manual recommends against flushing this transmission, but does have a procedure for flushing out the transmission cooling lines if needed. I hope your dealer isn’t doing this to you.

Here is a video supporting pan drop servicing and why you want to change your fluid filter every 30k. This is for the beginner.


Thanks transman; if flushing alone could clean the filter and flush out the debris in the pan we would not need to do this. However, this (dropping the pan) is what I ahve been doing for the last 44 years with good results. I regularly do the “blotter test”, put a drop of fluid on a paper towel. I should expand to the size of a silver dollar, and be a uniform pink color. No dirt should show up. If it is off color, I change the fluid regardless of mileage.