Transmission Flush Problem
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Joined: Sep 2012
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Transmission Flush Problem
I was trying to a transmission flush using the instructions here: https://sites.google.com/site/fordf1...nge-procedures
However, I was unable to disconnect the return line at the transmission ( I didn't have long enough wrenches to reach). Therefore, I disconnected the return line at the small box about a foot before it enters the transmission. So I disconnect the return line before if reached this small box, and install the 3/8" hose to go to my bucket. When I started the truck, transmission fluid was pumped out of the line, however it also pumped out the box where the return line was connected at about half the rate of the return line. This made a good mess, so I decided to try a different spot to intercept the transmission fluid return.
I went to the auxiliary transmission cooler, and where the fluid entered, I disconnected the line. I was able to route directly into my container with the disconnected line. Once again, the fluid came out of both the transmission line and the auxiliary cooler.
Why would the fluid pump out both sides of a disconnected line? And it wasn't just dripping out. I would get 3qts from the disconnected line, a 1qt from the cooler.
Could it be overfilled transmission?
However, I was unable to disconnect the return line at the transmission ( I didn't have long enough wrenches to reach). Therefore, I disconnected the return line at the small box about a foot before it enters the transmission. So I disconnect the return line before if reached this small box, and install the 3/8" hose to go to my bucket. When I started the truck, transmission fluid was pumped out of the line, however it also pumped out the box where the return line was connected at about half the rate of the return line. This made a good mess, so I decided to try a different spot to intercept the transmission fluid return.
I went to the auxiliary transmission cooler, and where the fluid entered, I disconnected the line. I was able to route directly into my container with the disconnected line. Once again, the fluid came out of both the transmission line and the auxiliary cooler.
Why would the fluid pump out both sides of a disconnected line? And it wasn't just dripping out. I would get 3qts from the disconnected line, a 1qt from the cooler.
Could it be overfilled transmission?
Originally Posted by downsjh
I was trying to a transmission flush using the instructions here: https://sites.google.com/site/fordf1...nge-procedures
However, I was unable to disconnect the return line at the transmission ( I didn't have long enough wrenches to reach). Therefore, I disconnected the return line at the small box about a foot before it enters the transmission. So I disconnect the return line before if reached this small box, and install the 3/8" hose to go to my bucket. When I started the truck, transmission fluid was pumped out of the line, however it also pumped out the box where the return line was connected at about half the rate of the return line. This made a good mess, so I decided to try a different spot to intercept the transmission fluid return.
I went to the auxiliary transmission cooler, and where the fluid entered, I disconnected the line. I was able to route directly into my container with the disconnected line. Once again, the fluid came out of both the transmission line and the auxiliary cooler.
Why would the fluid pump out both sides of a disconnected line? And it wasn't just dripping out. I would get 3qts from the disconnected line, a 1qt from the cooler.
Could it be overfilled transmission?
However, I was unable to disconnect the return line at the transmission ( I didn't have long enough wrenches to reach). Therefore, I disconnected the return line at the small box about a foot before it enters the transmission. So I disconnect the return line before if reached this small box, and install the 3/8" hose to go to my bucket. When I started the truck, transmission fluid was pumped out of the line, however it also pumped out the box where the return line was connected at about half the rate of the return line. This made a good mess, so I decided to try a different spot to intercept the transmission fluid return.
I went to the auxiliary transmission cooler, and where the fluid entered, I disconnected the line. I was able to route directly into my container with the disconnected line. Once again, the fluid came out of both the transmission line and the auxiliary cooler.
Why would the fluid pump out both sides of a disconnected line? And it wasn't just dripping out. I would get 3qts from the disconnected line, a 1qt from the cooler.
Could it be overfilled transmission?
Senior Member
Joined: Apr 2012
Posts: 1,425
Likes: 103
From: Vancouver, BC
Search this forum for proper instructions on how to do a transmission flush. Better yet, the actual transmission service is not a flush but simply replace the transmission fluid by dropping the transmission pan, replacing the filter and gasket (only if necessary) and then reinstallation of the parts and adding fluid. Having the transmission hot is pretty much a given, just like changing your oil and filter.
To answer your question, you probably had fluid between the lines somewhere. It's not a good idea to simply disconnect hard lines at different locations unless you were actually bleeding the system dry and replacing the lines themselves. Use the dipstick to check the level of your transmission fluid, and be sure to go through each gear (Park, Reverse, Neutral, Drive, Low 2, Low 1) before checking the fluid level. If you overfill it then you have to drain it all over again.
To answer your question, you probably had fluid between the lines somewhere. It's not a good idea to simply disconnect hard lines at different locations unless you were actually bleeding the system dry and replacing the lines themselves. Use the dipstick to check the level of your transmission fluid, and be sure to go through each gear (Park, Reverse, Neutral, Drive, Low 2, Low 1) before checking the fluid level. If you overfill it then you have to drain it all over again.
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Joined: Sep 2012
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More details
The transmission probably was still warm, but I tried to let it cool off so I could actually work underneath around the hot exhaust.
For clarity: I disconnected the return line back to the transmission, and when I started up the vehicle, fluid pumped from both ends of the disconnected line. So I reconnected that line, and instead tried at the Aux cooler. Same thing, fluid pumped out from both ends. Doesn't seem right. Fluid should flow out one side, and vacuum up the other. Why would it pump out both sides?
I was able to completly drain the transmission, buy starting the truck, pumping out 3qt, replenish the 3 qts, the repeat.
For clarity: I disconnected the return line back to the transmission, and when I started up the vehicle, fluid pumped from both ends of the disconnected line. So I reconnected that line, and instead tried at the Aux cooler. Same thing, fluid pumped out from both ends. Doesn't seem right. Fluid should flow out one side, and vacuum up the other. Why would it pump out both sides?
I was able to completly drain the transmission, buy starting the truck, pumping out 3qt, replenish the 3 qts, the repeat.