Just bought a 89 XLT automatic transmission with 4x4, was driving it home and the transmission just started grinding and blew randomly, it was driving smooth for about a half hour or so until then too so was weird

But I was just wondering if anyone knows what could of made it blow?

Also want to put a new one in just trying to figure out what transmission it is? found online that it’s a A4LD but I found that mustangs also have them and my trucks got 4x4 so wouldn’t that not work? If it does I found one some what near me for 200$ with 180k kms but wanted to make sure it would work or if not what transmission I have

Was also thinking maybe the transmission cooler went and caused it to blow so was thinking replace the cooler and get an extra one and have 2?

let me know what you think trying to get truck onto to the road engine runs strong and body’s in really good shape except box is a little rough