My idea for auto trans flushing....?

[SecondMonkey]

I've seen more than one post about making a transmission fluid exchanging "machine" that attaches to the cooler lines. The basic idea being, collect the dirty oil coming into the cooler and inject new fluid into the return line.

Let's say I take a 6 gallon pressure vessel, and fill it with about 4 gallons of fresh ATF. I would then plumb in a dip tube like a gas tank and pressurize the whole thing to 10-30 PSI(?) compressed air to push the new fluid into the return line. Collect the same amount of dirty ATF into a bucket.

Does anybody see any problems with this method? I have the parts laying around. What kind of pressure do transmission fluid lines normally run at?

I've been draining the transmission pan on my Jeep frequently (4 of 12 quarts) but am not happy with the results so far. I'd like to replace the fluid ENTIRELY...and I have more than one vehicle that could benefit from this.

 

[JTK]

I've done exactly that to fill the 'bottom fill' 4L30E equipped Isuzu products I've worked on. I used a sturdy gallon jug. Drill two holes in the cap. One for the "dip tube", one for a rubber tipped blow gun. You just need to make sure you don't get too aggresive with the compressed air or you'll make a nice exploding ATF water baloon.

Joel

 

[toyota62]

http://www.gadgetonline.com/TransFlush.htm

 

[cjhepburn]

I have an idea... You could take two 5 gallon buckets; a dirty fluid bucket and a fresh fill bucket.
The dirty bucket would have two fittings in the cover. One fitting would be the discharge from the cooler line. The other fitting would connect the two buckets together using a hose. The fresh bucket would have the one fitting in the cover and another fitting at the base of the bucket. The fitting at the base of the bucket would supply the fresh ATF to the transmission.
The idea is as the old ATF of pumped into the 1st bucket, it displaces air which is pushed into the second bucket which contains fresh ATF. The key is the two buckets have to be air tight.
I don't know if this would work in real life but to me, it sounds good on paper.

 

[CourierDriver]

I just had my dodge van b3500 transmission fluid changed, but did not observe it,,,what did they do in ur opinon besides flush and add new oil

 

[hate2work]

I think you guys are making this more complicated than it needs to be. There have been some good write ups/tutorials on cooler line flushes on this forum, find one and follow the directions.

 

[Donald]

Why not do it 2-3 QTs at a time and all you need is a 4-5' piece of clear hose. Best if you can drain and refill pan before starting. Let the transmission pump do the work. It will anyway.

The flush machines are so the mechanic can do something else for 20 minutes.

 

[mechtech2]

Sure , that system could work well.
Those lines can reach high pressure under some conditions.
Figure 30-70.

 

[qship1996]

Just drain/fill it 4 times and you are at 90% new fluid- simple,cheap,and effective- after that, just 1 simple drain/fill every 15,000 miles will be more than necessary to properly maintain it for life.