if you see metal chips in the pan and have a non moving transmission there is definitely going to be metal in the ATF cooler, you can backflush the cooler with warm ATF first (assisted with compressed air) and finish off with LubeGard Koolerclean. It can really flush out junk. You can also get your radiator to a trans repair shop who have a cooler cleaning machine, this machine pulses hot atf into the cooler circuit agitating it back and forth to loosen debris.

The torque converter can be cleaned if you are willing enough, its a very long and slow exercise with ATF, gasoline, an input shaft and lots of sloshing around. Or you can just buy a replacement rebuilt converter - make sure its the same part number.

The kits for rebuilding are of very good quality, borgwarner/raybestos/alto/allomatic all work great. If this is your first attempt, do it in pieces so you keep track of whats what. I would also suggest you to buy some bench buddies (brushes) to clean the valvebody bores, they are fantastic for this job as they polish the bore just enough to allow the valve to drop in smoothly under its own weight.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)