the 4R100 in my F250 has been leaking, well not leaking but a few drops on the pan, since I got it from my cousin back in November. Crawled underneath yesterday with my torque wrench to see if any were loose, most of them were loose, I tried tightening them to 125 inch pounds and I could only get a few turns on one bolt before the gasket( cork gasket and looks to be the original) cracked and started pushing out from the side of the pan(way before the wrench clicked, and 125 inch lbs isnt much). I'll pick up one of the updated reusable Motorcraft gaskets from the dealer Thursday, and change the gasket and filter along with a drain and fill of the fluid. Hopefully it can last until I have time to pull it out and build it. I'm not hard on the truck, most shifts are at 2k rpm and the other day I floored it to 3k, I dont do it often, for being an old tranny with the miles on it it still shifts well. my question is, I've heard I can run Dexron III/Mercon in it, and also Mercon V. Some say not to use Mercon V in the 4R100, while others say Ford changed the formulation and its now compatible with the 4R100. I was thinking of going with Supertech for the Dex III/ Mercon or Supertech Mercon V, would that be a good choice or should I get a different brand? Are Supertech trans fluids good? Should I use Dex III or Mercon V? Thanks
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