not shifting into 3rd

[GTDrifter]

My brothers 97 Impreza auto will not shift into third. It shifts into third but as soon as you hit the gas it'll either floor it in second or shift into neutral. It does this whether you push heavy on the throttle or gentle. Any help is appreciated.

[Huffer]

Torque converter isn't locking up, or the car is in limp mode. Any CELs?

[GTDrifter]

no check engine lights.

I was thinking torque converter because it doesn't seem like the transmission is blown like Nik's outback. My cousin said it might be the valve body but I don't know much about transmissions. He was low on tranny fluid and said he put some in but I haven't checked the levels myself.

[Huffer]

I'd check the fluid levels and the condition of the fluid. I doubt it's the clutch packs.
If the torque converter had no fluid in it then that would cause some shifting issues for sure.

Drain the AT, then refill 90% and check for leaks. You could then throw in some LubeGard ATF Protectant for good measure.

[GTDrifter]

I'll do that whenever I get time. The only part of the car that moves is the driveshaft sitting in my moms truck