Advice: 2002 ford mustang transmission overheated

My 2002 mustang with 97k miles just had what has been described to me as a severely overheated transmission. The O/D OFF light was flashing and I noticed some faint smoke and a terrible odor from the burning transmission fluid. I was told by a nearby transmission specialist that it would cost $2500 to rebuild the transmission and put in an external cooling device (which he said was necessary). I am now weighing the following options and am hoping for some help: 1) pay for the rebuild and trust everything will be fine, 2) have the transmission replaced (if it overheated as much as they say I’m wondering if anything has warped and will lead to problems down the road) or 3) try to sell or trade in the car for something new (i’m not sure if it is worth much of anything now…). I don’t know much about cars so any help is appreciated! Thank you in advance!

Has the transmission fluid and filter ever been serviced?

If not, it was way overdue

Were you driving really hard when you smelled the fluid burning?

I don’t have my service records but I am fairly confident it was changed around 60k miles. I was driving in stop and go traffic in the middle of San Francisco for about an hour before it started overheating.

Were you towing something?

If it overheated without driving hard or towing, it had to be slipping badly creating that heat. It likely needs a rebuild but less likely to need an external cooler. If the radiator has transmission lines (much smaller than the radiator hoses with a metal fitting on the end) going to it to cool the trans be sure to have it checked. It may be filled up with shredded transmission bits. Your mechanic may figure an external cooler is cheaper than replacing the radiator.

And 1) a rebuilt trans should be OK or 2) It might be cheaper to install a used transmission - but less reliable and 3) A broken car is most always worth less than the repaired sell price minus the repair.

Is it currently drivable? If not, option 3 is going to be salvage pricing. Option 2 then becomes very desirable because used transmissions are a lot less expensive than rebuilds, and the car is 12 years old. Compare the value of the car to any repair option to determine if it is worth the effort.

Assuming the car & engine is in good shape otherwise, no rust issues, body integrity is good, no signs of cat or ECM failure, etc. Provided that’s the case, seems to me $2500 is a lot less expensive than buying a replacement car. I’d be inclined to just have it rebuilt. A fair price, esp if it includes a transmission cooler install too. If the overheating severely damaged the transmission, they’ll notice that during the rebuild. Not likely though, probably just the internal clutches are worn is all.

Did the mechanic recommend an external cooling device because of a faulty radiator transmission fluid cooler? A faulty radiator cooler can wipe a transmission out pretty quickly by allowing engine coolant to mix with the transmission fluid.

The price sounds fair and the car should be well worth repairing as a 2002 with only 97k miles is a puppy.
The external cooling device mentioned is basically a small radiator that is used only for cooling the transmission fluid.

The external coolers work very well and they not only cool the fluid much better than the stock radiator cooler but they also prevent the possibility of engine coolant and trans fluid ever mixing again.

Just stay away from the chain transmission place whose name stands for All Automatics Must Come Out!

I think I’d just change the fluid. Do a drain and fill one time and make sure the cooling coil in the radiator is clear and if the transmission works good, change the ATF again in a week and again a week after that. If it doesn’t work well after the first ATF change, then don’t bother with anymore changes, just get the overhaul.