Anyone have any idea what this metal valley that runs through the tail housing of the transmission is for? on my other trans this piece was all bent up and wasn't allowing me to install the tail housing and align the shifter rod correctly... I tried for hours, but after removing this piece I was easily able to install my tail housing... is this piece important? should I reinstall it and try again?

 

That trough is there so that the gears can slop oil into it while you're driving and it can pass oil back to the rear bushing so it doesn't oil starve. Thats why you pull the driveshaft before you tow a car. With the car in neutral, it can't sling oil to the back of the transmission, and you'll burn it up unless you disconnect it from the differential. Mazda didn't put any extra parts in the transmission, put it back.

 

Appreciate it, I will try and bend the one on my other trans back to shape and install it