I was dropping the pan on my 04 Lariet to change the filter when this round yellow thing with a rubber o ring around it and a stem on the bottom of it, just fell out. I have no idea where it came from or how to put it back. Please help, this is currently my only vehicle. THANKS!

 

No worries, just throw it away. Its the knockout plug for the dipstick hole when the tranny was assembled. When they put in the dipstick on the assembly line that plug just falls down into the pan.

 

OMG! You just found the Holy Grail of prizes offered by Ford! Take it to your nearest Ford dealer for your reward! If you get there quick enuff you might get the grand prize!

Someone needs to make a sticky about this!

 

Use it for a bobber next time you go fishing.