Hi Newbie saying....erm...hi.....

[David]

I guess may be best to have the whole lot changed for Motorcraft Mercon-V in the same way and HOPE it does it. I am in no way qualified to say that though, just thinking out loud. Consulting Brian (scooter) may be a good starting point? Do not drive it would appear sensible for now!

Edit: There-after sue your garage!

David

[Nich]

A post from 3 years ago:

Isn't the autobox the 4r70w? If so you must use Mercon V, Dextron III is not a substitute for Mercon V but _IS_ for Mercon, using it will cause your box to fail.

I have a 4r70w in my New Edge Mustang and went through this pain. Interestingly my stang is supercharged and the 4r70w holds up like a champ many owners saying they are stronger than the manuals. Did I read on here that the R75 couldn't be charged due to gearbox weakness?

[SCP440]

I have a freiend in Oxfordshire who specalises in Auto gearboxes, if there is a problem he will know what the issue is and can probably come up with a solution.

Let me know if you want me to put you in contact with him.

Steve

[David]

Looking on various forums, it would appear that Mercon V contains a special "friction modifier" which is necessary to allow the special friction clutch material to function properly in our boxes (4R70W or 4R75W). The slippage mentioned could well tie in with that description of what the 'V' does that Dexron or normal Mercon does not?

David