ATF change scenarios.

[Donald]

I have been a shadetree flush kind of guy on all my vehicles going with Amsoil ATF. The method uses the least expensive ATF to do a total fluid exchange.

But I was thinking that when you do a flush and the ATF does some cleaning (if its needed) the cleaned up crud will stay in the transmission (or if lucky my Magnefine filter) for 50K until I do another flush.

But if I do several drain & fills with say 500 to 1000 miles between each then the new ATF will have some time to clean up anything there and a portion of the cleaned up crud will be dumped with the next drain & fill.

Of course this may be pure theory and it never happens in real life.

I am still not convinced that a shadetree flush will cause harm. And most transmissions seem to look spotless when the pan is dumped.

 

[Dave Hess]

I do 40K mile drain / refills without a Magnefine.

Clean fresh ATF is what will keep *most* transmissions running smoothly.

 

[Quest]

@ OP:

Your drain-n-fill method is sound.

I've done this over the years on numerous vehicles (with the exception of one which the A/T gearbox and the torque converter came out for service anyways), and they are all fine to this day.

Q.

 

[LeakySeals]

I perform a drain and fill every spring in the old Camry regardless of miles. After 5 years using this method it comes out "looking" the same as when it went in. Clean and red, no visible crud. Never been apart, still has original screen filter. No issues. The transmission and engine are going to outlast the body which is in decline.

 

[Donald]

My point or question is, could this be a better way than a flush since in the end you will be dumping out ATF with anything that new oil cleaned up. Or at least a lot of it.

 

[SargeBB]

Originally Posted By: LeakySeals
I perform a drain and fill every spring in the old Camry regardless of miles. After 5 years using this method it comes out "looking" the same as when it went in. Clean and red, no visible crud. Never been apart, still has original screen filter. No issues. The transmission and engine are going to outlast the body which is in decline.

My old work car is a 1996 Camry V-6 with over 290,000 miles (541E A/W transmission). I do a pan drain every 15,000 miles using Mobil 1 ATF. Like LeakySeals, the drained fluid (which is around 2 1/2 qts.) is cherry red and the transmission shifts as well as it did when I drove it brand new off the lot in Jan., 1996. This car has operated its entire life in one of the dustiest environments in the USA and the car does NOT get 'petted.' 75 to 80 MPH on the highway with several 2,000 - 3,000 mile trips annually. Body is still almost perfect. Quite frankly, I prefer this old car to my wife's new Camry V-6.
Common-sense, easy maintenance plus an almost bulletproof drivetrain allows for unbelievably long and trouble-free vehicular lifespan.

 

[threeputtpar]

Originally Posted By: Donald
My point or question is, could this be a better way than a flush since in the end you will be dumping out ATF with anything that new oil cleaned up. Or at least a lot of it.


Yes, if your goal is to make sure you get out any and all of the suspended debris then the pan drop with a filter change is the best method.

If you're also looking to get the maximum amount of old fluid out too, then the only tradeoff will be that you'll use more new fluid to completely replace all of the old fluid because with each pan drop you'll dump a percentage of the new fluid.