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To flush or not to flush


Guest ScoobieNoobie
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Guest ScoobieNoobie

What are your thoughts on a power flush of a 3 speed auto. transmission? I have heard some good things and I have heard that just a regular drain and fill is better for it.

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Guest snotrocket23

Well, you can't go wrong with a drain and fill. I guess the theoretical adverse effect a power flush might have is to loosen up grit and shavings and reintroduce them into the hydraulic system. Kind of like cholestorol and a stroke. It's fine if it doesn't move around. But all you need is a fleck of junk to hang up a valve in the valve body. On the flipside, I had the BW 66 in my Jag power flushed (and I don't think it got much service from the previous owner) and it shifts great, even w/ 200k. I belive the filters should be changed fairly regularly, but there is a lot of mist surrounding the subject of a/t maintenance, fluid, filters, mileage, etc.

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Guest thealleyboy

I wouldn't do the flush unless you know the history of the car, and the tranny was not neglected previously.

 

If the fluid hasn't been changed for 75k or more, forget it.

 

Everytime I've done this, the tranny junked out soon thereafter.

 

John

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Guest thealleyboy

Jay:

 

All A/T's seem to react adversely to a fluid change (flush), after being neglected for a long period of time.

 

Some people dismiss this as urban legend. I know better from experience. It's happened to me on two vehicles - a Chrysler and a GM. Both had low miles, but had been neglected.

 

I've heard all kinds of theories. One of the more interesting ones is that the new ATF "rejuvinates" old brittle seals and gaskets, causing them to fail. The old ATF is supposedly more compatible to the system as a whole.

 

Use your best judgement, but be careful...

 

John

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There is NO power in Power flush

The tranny hyd. pump does it all.

The line to the tranny cooler inside the rad is disconnected and the new fluid container is spliced in line with the cooler.

The engine is started and the old fluid displaces the new in the container and the new is pumped (via the cars tranny) into the system.

I had this done on my EA82T 3 speed wagon with no ill effects, the shifting seemed to smooth out but my problem was the governor wanted cleaned and deburred.

 

The idea is that the torque converter holds several quarts of fluid and to change all of the fluid is better than changing just the half that is in the pan. Would you change only half your oil?

The filter (under the pan) is just a fine mesh screen and can be cleaned with compressed air and kerosene.

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