I put a used 4R70W transmission in my 2003 F-150. Unbolted the oil pan and pulled the filter straight down and laid it in the oil pan. When I poured the oil from the transmission pan into an oil bucket, this yellow plastic plug with a stem fell out of the oil filter. I guess it goes back into the spout that pushes back into the valve body.

Question is, does this yellow part go in with the stem facing out of the spout or the stem face toward the inside of the filter.

It's has an o-ring around it, but it fits very loosely in the spout either way. Is it suppose to?

Please help.

 

Cannot believe anybody hasn't jumped in yet on this.
It is a temporary plug installed in the dip stick filler tube hole in the transmission by the manufacturer.
During vehicle final assembly, when installing the dip stick tube, it is pushed into the pan.

If you found it in there, it means (most likely) that the pan has never been removed from that transmission before.

 

Wow, you are amazing. The plug is gone and I can finish my install.

Thank you so much

 

Thank you, Dialtone. I dropped my Expedition's pan yesterday, and was scared so much because of this yellow piston part. I didn't know how or where this part goes back to. I checked the service manual to no avail info. Finally, I checked with a local Ford dealer parts clerk, and he checked with a mechanic who said that the part could be tossed, but did not explain it's from the tube. So I was half relieved that I didn't do anything wrong to get the part dropped down, but still was not sure where it came from.
You made it clear, and I fell confident to discard it.

 

PS: Strange thing is that my Expedition is at 60,000 miles now, and when it was 30,000 it was taken to a dealer to do a "transmission flush" which costed $184. But the plug has been in the pan since!

 

the never pulled the pan or changed the filter... they connect an external pump and push fluid around the sustem till it comes out clean, then refill.

 

I'm doing my tranny fluid/filter today and found the same piece. Pucker factor went up to around 9.5! Thanks for clearing this up for us!!!