JD444a transmission problem

Hi all and thanks for the add. I have an old 444 that has always been a little slow moving if at all when cold, well this last weekend during the snow one of the operators called me and said it stopped moving so I told him to get into another loader and I will check it when I can ,forgetting common sense is learned and not normal lately I got to it about an hour later and noticed he left it running, I shut it down and started looking and the trans cooler had blown an oil line so sat there for an hour running dry. I took a shot and repaired the line added fluid and nothing, no steering or moving. The bucket moves but thats all. Think I should pull the HP pump on top of the trans and take a shot or is cooked throughout. its probably not worth rebuilding the trans. I put a new hydraulic line on the loader bucket earlier that day at a price of 800 bucks but I cant change that lol