Its been known to happen with these cars.

If you have the time and ablility I'd pull your old trans out and have it rebuilt. The radiator you have got to replace their isn't much you can do about that. Just make sure to flush the cooling system well to get all the oil out of it. Also make sure to flush all of the old trans fluid out off the cooler lines so you don't screw up your freshly rebuilt trans.

How does the tranny fluid look? I'd think it should look like a strawberry shake with coolant in it.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200