727 transmission problem

Have you checked the radiator to make sure it has no transmission fluid? As if the cooler in the radiator is compromised? What does the fluid look like on the dipstick? Is it nice and red? Does it smell good like new fluid or burnt? Have you tried manually shifting to first gear to see if it'll pull?
No cooler for the transmission, oil is dark red on stick,i have a channel on YouTube, tm I'll post a video, can you guys plz watch it and tell me what your advice would be