I'm going to be flushing the system is it still ok to use mercon/ dexron or do I have to use the mercon v? I would rather go with the cheaper option.

 

You get what you pay for. MERCON V is superior to DEX/MERC, which may or may not meet the now discontinued MERCON rating. It's your transmission, you don't HAVE to use either.

 

I will use mercon V if that's what it needs but if mercon/dexron was still acceptable I would use it. What about the transfer case?

 

I use Valvoline transfer case fluid. The are stories about transfer case case's being broken from the use of Mercon V but I don't believe them. Ford also has a transfer case oil that they call for now. Opinions will vary.

 

I have a 2002 manual and shift on the fly.

Dexron 3 is fine by me in tranny and transfer case as that is the spec called for. YMMV but I doubt it.

 

Mark would the super tech Walmart brand mercon v be ok to use? I'm guessing as long as it's mercon v it meets the ford specs?

 

I used the Supertech Mercon V this last trasmission / transfer case flush. I personally haven't had any issues. I just couldn't spring for whatever was at Autozone at twice the price.

 

The problem is that nobody produces DEXRON III or MERCON any longer. There are many fluids that say they are for use in transmissions that used DEX or MERC, but what spec are those fluids produced to? Nobody knows. Ford stopped licensing MERCON, and GM stopped licensing DEXRON III. Both are obsolete specs. MERCON V has replaced MERCON. Ford licenses MERCON V and monitors the fluids to ensure they meet the spec.
Yes, it's fine. In order to say MERCON V on the label it has to be certified by Ford to meet the MERCON V spec.