Synthetic vs. Conventional Trans Fluid

[Mejium]

So I'm about do for an AUTOMATIC trans fluid change, and I don't know what was previously in it. So I was wondering would it be better to put conventional or synthetic in after the fluid is changed. I plan to drain it, fill it, drain it again, and fill it again and add lube guard. Anybody have any brand recommendations?

[Huffer]

You can use whatever meets the DEXRON standard for the Subaru transmission. Throw some LubeGard ATF Protectant in there as well to help lower temps. In an auto, high temps = premature death.

The 4EAT isn't particularly choosy over synthetic or regular. I've saved 3 Subarus with varying mileages from torque bind with the cheapest ATF + Lubegard ATF Protectant.