I want replace the PS fluid on my 2010 FX4 and the owners manual calls for MERCON V however for auto trans it calls for MERCON LV (don't know the difference between them, if any).

Can I use any brand of ATF (ie. Delco, Penzoil, etc) or does it require a particular specification?

 

Use what the manual recommends. My truck uses Mercon V in both because it isn't the 6-speed. You can use any brand you wish, but just make sure that it meets Ford spec. Why not just go to the dealer and get Motorcraft? It isn't that expensive.

 

I have left over ATF (still in sealed container) from another project and wanted to use it up but you may be right to just stick with the Motorcraft.

 

Did you mean to say you want to change your transmission fluid? Technically ATF would work if you needed to use it in a pinch, but I would suggest replacing your power steering fluid with new power steering fluid.

 

I want to change out the power steering fluid and the Ford manual specifies Mercon V trans fluid.

 

ANY brand ATF that meets Mercon V specs is fine, I use Mobil 1.

 

As a suggestion, you might want to consider Castrols High Mileage ATF Mercon V for your power steering. It has seal agents in it that will keep the seals nice and supple extending the life of the power steering system.

In regards to the LV ATF, it is not compatible with regular Mercon V. The LV stands for lower viscosity, meaning it's a thinner fluid. It's what makes the newer transmissions work better. Here's some reading for you:
http://www.imakenews.com/lng/e_artic....cfm?x=b11,0,w

 

Well, I learned something today.

 

I dropped in to a dealer on my way to the cottage this afternoon to pick the Mercon V and ended up walking out empty handed because not one of the 4 parts guys standing around and in plain view of me would even give so much as a glance to acknowledge my presence.
Talk about feeling less than, walking out nobody said a word but I was happy not to give them my business today or ever. And now that I just read Laberd's post about Castrol I'm even happier I didn't pickup the Mercon.

 

You can get good fluid that meets specs at Walmart. The dealer is the LAST place I'd buy routine maintenance items and supplies.