Transmission fliud

My operators manual calls for Dextron II hydraulic fluid. When I went to purchase some at the auto supply store they told me this was obsolete, and that I needed to use Dextron III fluid as it was the same. Are they the same? Can I use Dextron III

And Dexron III ( there is no T in Dexron ) is replaced by Mercon which is now Mercon V.

Old owners manuals can’t get updated as the industry changes so you’ll have to write it in. ( Kinda like mom’s old reipes that call for that 16 oz can of tomatoes that you’ll never find in the stores now that they’re all 14 or 28 oz. )

Dexron III replaced by Mercon? Mercon is the Ford transmission fluid, Dexron is GM.

Google “Dexron II replacement”.

I Googled “Dexron III replaces” and found a site that said Dexron IV replaces Dexron II and III.

PS, read the bottle label; might have your answer too.

You need to give the year, make, model of the car.

Neither Dexron II nor Dexron III are licensed by GM anymore (Dexron is GM).

The latest GM spec fluid is Dexron VI, and if yours called for Dex II you can use Dex VI.

Or you can use most any of the “Dex/Merc” fluids (good for Dexron & Mercon applications). Read the bottle and it will give you what it is good for.

Thank you for the feedback, much appreciated.