Forum Discussion

path1's avatar
path1
Explorer
Aug 21, 2014

Mercon and Mercon 5

From 2003 owners manual...

"Some transmission fluids may be labeled as dual usage, such as
MERCON and MERCON V. These dual usage fluids are not to be used
in an automatic transmission that requires use of the MERCON type
fluid. However, these dual usage fluids may be used in transmissions that require the MERCON V type fluid.

MERCON, MERCON V and MERCON SP are not
interchangeable. DO NOT mix MERCON, MERCON V and
MERCON SP. Use of dual usage fluids in an automatic
transmission application requiring MERCON SP may cause
transmission damage. Use of a transmission fluid other than the
recommended fluid may cause transmission damage."

My dip stick say Mercon. Engine is 5.4 gasser with a 4r100 trans, that I believe has been re-built.

I use Mercon V. Back of bottle basically says..good for both.

What am I missing? Maybe 2003 info (older and outdated) and maybe newer stuff on market now?

Thanks
Tow Vehicles

4 Replies

  • path1's avatar
    path1
    Explorer
    Aug 22, 2014
    Mark Kovalsky wrote:
    path1 wrote:

    What am I missing? Maybe 2003 info (older and outdated) and maybe newer stuff on market now?

    What you are missing is that in 2006 ford discontinued licensing MERCON. They changed the specs for MERCON V to make it compatible with transmissions that used MERCON. MERCON V is now the correct fluid for use in any application that used to use MERCON.


    Thank you
  • Mark_Kovalsky's avatar
    Mark_Kovalsky
    Explorer
    Aug 22, 2014
    path1 wrote:

    What am I missing? Maybe 2003 info (older and outdated) and maybe newer stuff on market now?

    What you are missing is that in 2006 ford discontinued licensing MERCON. They changed the specs for MERCON V to make it compatible with transmissions that used MERCON. MERCON V is now the correct fluid for use in any application that used to use MERCON.
  • dodge_guy's avatar
    dodge_guy
    Explorer II
    Aug 21, 2014
    There was a TSB issued by Ford years ago that states that Mercon V is OK to use where Mercon was originally used. The Mercon SP is completely different and should not be used where Mercon and Mercon V are used!
  • Campfire_Time's avatar
    Campfire_Time
    Explorer
    Aug 21, 2014
    Call a dealer service department. I can tell you that GM switched to Dexron VI in 2006 and its backward compatible with older transmissions. In fact its recommended. If you take a pre-2006 to a GM dealer for any transmission work or maintenance they will use Dex VI.

    I would imagine that its the same for Mercon V, but it sounds like the label is clear as mud.

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