Mixed 1qt atf+4 w/dexron3 in 727......

[JPL]

I went to the parts store and was told that would be ok, so I put 1qt of atf+4 tranny fluid to top off my 1971 727 that is almost full of dexron3, I was told that would be ok, is that true?

[Plumcrazy]

ATF+4 is backwards compatible. If you wanted to, you could completely replace the Dexron with ATF+4

[JPL]

ATF+4 is backwards compatible. If you wanted to, you could completely replace the Dexron with ATF+4

Thanks Plum!

[John_Kunkel]

Truth be told, you can mix any ATF without fear.

[c00nhunterjoe]

Truth be told, you can mix any ATF without fear.

the parts stores won't like that!

I am curious what effect ford's mercon sp will have on the other tranny's. That stuff is specific for the 5r110 trans and ford is extremly clear NOT to mix it in any other trans.

[flyinlow]

Used Type F with shift kits in 727 's to help make them shift crisper.

[JPL]

Used Type F with shift kits in 727 's to help make them shift crisper.

I heard that before, I might do a swap in the future.

[c00nhunterjoe]

I ran type f in my auto and can't really say I notcied any difference.

[John_Kunkel]

I am curious what effect ford's mercon sp will have on the other tranny's. That stuff is specific for the 5r110 trans and ford is extremly clear NOT to mix it in any other trans.

SP is just a synthetic Mercon, like ATF+4 is to ATF. Manufacturers warnings are a lot like religion, they use fear to push their agenda.

[c00nhunterjoe]

What's the difference in merc IV to merc V?

[HeavyFuel]

Truth be told, you can mix any ATF without fear.

Synthetic...non-synthetic.....doesn't matter?

I ask because I filled my converter before installing it to the tranny...to the engine..into the car.

Now I'm not sure what kind I put in.  I think it's Lucas semi-synthetic.  Says it's compatable with just about everything.

John....so I shouldn't worry, just add in more of something close?

EDIT---I just read a bunch of other threads...got the answer...thanks.