Which hose to disconnect when changing the ATF?

[petero]

I'd like to do an ATF change, and I'm following the instructions in the FSM.  It says to disconnect the hose shown in the diagram, but there are two hoses shown here.  Do they mean the one thats darker than the other one?  Also, when I disconnect the hose and run the engine to drive the fluid out, will it come out of the hose, or will it come out of the metal tube?

Thanks,
Peter
1999 MS LTD

[mudrunner]

yes they mean the on that is highligheted. As far as where it will come out, I would just make sure your bucket is under both! lol otherwise I would think the hose since it will most likely be flushing the line from the Radiator where the cooler is.

[petero]

Cool, OK thanks, that makes sense.  Now here's another question:  Check out the photo below.  The green arrow points to the other end of that hose, where it connects to the radiator/atf cooler.  This is right up under the bumper on the passenger side, and there's really easy access to it.  Wouldn't it be easier to disconnect the hose here, and then push another hose onto the outlet tube with the other end of the hose in my bucket?  That just seems easier than crawling up under there to make sure the hoses are secure and where they need to be.

[mudrunner]

Try it I don't really know what will happen. Never hurts to find a short cut. That is what working on your own car is all about!

[petero]

Alright, I'm done.  It turns out the flow goes the other way.  As far as I can tell, that hose that is bold in the drawing above carries fluid from the transmission to the atf cooler/radiator.  When I pulled the rubber hose off the bottom of the radiator and started the engine, the fluid pumped out of the rubber hose and not the cooler.  So what I did was to pull the rubber hose through towards the back of the car to give me some free length, then I pointed it down into my bucket.  At that point, I followed the instructions on page 23-45 of the factory service manual.  See the photo below. It all went pretty well, and only took about 20 minutes from start to finish.



I chose not to change the atf filter, since the transmission is shifting very well, the old fluid was still reddish, I'm lazy, and there are absolutely no leaks right now (and I know that if I pulled the atf fluid pan, it would probably leak after I was done). I only changed the fluid because the truck is fairly new to me, and I'm unsure of it's history. I know the fluid was changed 40,000 miles ago, but there are no other records.

I ran two purge/fill cycles, like the FSM says, and emptied the pan from the drain plug.  The fluid was running clean red at the end of the second cycle, but I'm sure it was contaminated with the old fluid from the cooler.  I think that's OK, since the old fluid was still reddish, and the transmission shifting well.  I changed exactly 8 quarts in the process.

[mudrunner]

Probably why they have you do it from that end is so you can flush the cooler as well.

[CoreyJ]

I've got to say, nice job petero! The very word transmission scares me lol. This is one job that I did go right to the pros on. Cost was $215 for flush and fill with new filter. I'm satisfied. The Monty drives a whole lot better now.

[sport03]

I need to change my fluid but it hasnt been changed in more that 100,000 miles due to neglect of the previous owner