My car has been leaking transmission fluid, but I can't find the leak.
There could be many areas where you may be seeing transmission fluid leak. Leaks can come from bad seals, a damaged pan gasket, or cracked fluid lines. Only a complete inspection of the leak will help determine where it’s found. A mechanic possibly adding oil dye to find the leak with a black light leak detector. I recommend having a certified mechanic, such as one from YourMechanic, come and locate the leak and make the necessary repairs.