in our shop we use dexron II and up (Dexron III, Mercon, Mercon V) for Galants. Always remember that if you're car is mandated to use Dexron II, you can only use Dexron II or higher types of ATF.

To give you an example, 1-lowest 5-highest

1. Allison c4
2. ATF - HDP
3. Dexron II
4. Dexron III
5. Mercon
6. Mercon V

If your car's OEM ATF is Alisson (or Diamond for that matter) you can only use Allison or higher. If your car is rated Dexron III, you can only use DexIII, Mercon & Mercon V.

Caltex have stopped refining Alisson C4 last year.

Can you tell me what happened to your car? Your details are a bit fuzzy. Why did you undergo ATF replacement? What are you experiencing now? Shift Shock? Shift Lag?