Wanted to run this by the tranny people and get opinions on it.

A little while back I decided to replace the ATF fluid in my Ranger (5R55E). I dropped the pan, drained as much fluid as would come out, replaced the filter, and put the pan back on.

I really wanted to get all the fluid out, but as you know, there is no torque converter drain plug in the 5R55E tranny setup. But while I was under the truck I had an idea. I took off the hose connections that run to the tranny cooler (my Ranger has another cooler in addition to the stock one). I then stuck one of the hose ends onto my compressed air trigger bit (nice tight fit). I put the other hose end into a waste pail. Then I slowly but methodically pulled the trigger forcing air ithrough the tranny system. The objective, of course, was to blow the rest of the fluid out. And I have to say, it worked pretty darn good! I almost ended up blowing out as much fluid as had come out when the pan came off. By virtue of how many quarts I had to replace, I know I got over 90% of the old fluid out by the time I was done. Worked kinda like my own flush system, so to speak. Anyway, to make a long story short, I am very pleased with the new fluid and filter, the tranny shifts much better, and it really wasn't that hard of a thing to do since I had the hose ends right there.

So, what do you guys think? Good idea or bad? I gotta believe it's as good or better than starting your engine and letting the pump blow out the old fluid, which is one of the other methods that people use.

So let's hear it.

 

There is another method in the Tech Articles section. It was posted July 6, 2002.

 

bad , very bad

i think i would have got two 5 gallon buckets and filled one with fresh fluid, disconnected the return line and inserted it in the bucket with the fresh fluid, next i would put the other line in the empty bucket, then started the truck and let it run untill all the fresh fluid was out of the bucket.
you with me here?

let the trans pump do the work, forcing air in is not a good idea.

we have a "T-TECH" trans flush machine at my shop and it basicly works the same way as i stated but not so primitive.

 

Will there be suction on the return line to the transmission? I thought there was only pressure from the output line going to the cooler, and this is what moved the fluid through.

 

Mark, I was hoping you would respond. I did read your article before I attempted the tranny fluid change. It was actually my game plan going in to follow your methodology. However, the problem that I ran into was that, for the life of me, I couldn't get at the tranny return line! Just could not get a wrench on it where I had the proper leverage (actually, no leverage). Even then, I was wondering how I was going to be able to work with the line once it was disconnected. There just wasn't any room to get my hands in there. And, I wasn't going to risk stripping or breaking anything. In fact, it was at that point in the process that I realized that I had to try something else.

Maybe someone with a 4x4 Ranger with the 5R55E who has done it your way can let me know how they were able to get the tranny line(s) off and work with them?

Diesel, I gotta admit, after I did it I felt kinda guilty, like maybe I had gotten away with something. Then I found out later that Ford has a cleaning and backflushing procedure in its Factory Repair Manual for the 5R55E tranny, and one of the steps is to blow out the tranny lines with compressed air once the cleaning solvent is run through the system. So in light of the fact that Ford says it's OK to use compressed air in that situation, I really don't see why it wouldn't be OK to use it in the manner that I did.

Thanks for the replies guys.

P.S. I am interested in more opinions if they are out there.

 

I was with you until the sucking out of the bucket thing. There is no suction in the return line.

The difference between the T-Tech and your method is that the T-Tech has a piston in a cylinder. As the old fluid fills one side of the piston it pushes the piston down, which forces the new fluid in the return line.

 

your right , i was half asleep when posting