Trans fluid flow direction

[gunnerbob]

I'm planning on doing a compelte flush of ATF on my 94 4WD. I followed the cooler lines from the transmission to the front, and the line which is closest to the pan goes to the top of the driver's side of the radiator. Another line exits the bottom of the radiator, then goes to the driver's side of what appears to be an external trans cooler mounted in front of the radiator. Another line exits the passenger side of this cooler and back to the transmission, entering above the first line.

Here are my questions:
1) Does anyone know which way the fluid goes, i.e. radiator then cooler or cooler then radiator?

2) Could I connect an extra length of line to the existing line between the transmission and the cooler, so that the old fluid is forced out through the cooler, and new fluid is sucked from a bucket through the extra line back to the transmission when the engine is running?

3) Is this idea crazy?

Bob

 

[MrShorty]

Someone on here described the procedure fairly well several months ago. users name was ROBERT I think. I found his post through the "search" function.

 

[RTStork]

Here is the post I made on another thread on how to change the ATF:
Changing the fluid is easy. Here's how I did it:
I disconnected the upper transmission line going into the cooler inside the radiator. I then slipped a rubber hose over the end of the connector on the upper transmission line and route it to a bucket which I already had marked in 1 qt increments. I then started the engine and the fluid pumped into the bucket. At the first sign of the flow starting to back off, I shut the engine off. By shutting it off as soon as flow slowed down, there is no damage to the transmission pump. Now that the transmission fluid is pumped out you have the option of removing the pan and changing the filter. The filter is just a metal screen and every time I have looked at it it didnt have anything on it, so its up to you whether or not to change it. I personally am not going to remove the pan anymore. Your best bet is to use a external oil filter, which will actually filter smaller particles. Reconnect the upper transmission line and add the exact amount of ATF that you pumped out and you are done. Removing the pan only gets out about 4 qts, so this is a great way to get all the fluid out without paying a place $75-$100. Since you may get all of the ATF out or there may be a 1/2 qt left in the transmission, I recommend marking a bucket in 1 qt increments and when the flow starts to stop, shut off the engine. Its the safest way to prevent damaging the transmission. Since every last drop will not pump out, I would go by when the flow starts to stop rather than waiting on a specific amount to come out. This is just my extra precaution to prevent damage. Let us know how it goes.