Mixing synthetic with conventional

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schroederMP

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I about to change my tranny fluid. My tranny was built by the previous owner...and I'm unsure what the shop put in it as far a tranny fluid (they have failed to call me back)


My question is... lets say they put conventional tranny fluid in it, then I put synthetic fluid in it when I change it. Will that hurt anything?

I'm not flushing, just changing the gov selinoid and filter.

Dont wanna fry my tranny...do expensive to do guess work.

This might be a dumb question...but I cant figure it out!
 

Hammer_Z71

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Any oil that conforms to the recommended ATF +4 standard is 100% compatible. You can mix and match as long as it is all ATF +4...
 

Uncle Ugly

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Mixing with regular trans fluid as stated will not be an issue as long as whatever you use is rated ATF+4 or better.

It would be a better option if you would flush the system to some extent with whatever your planning on using after the work this way the fluid is all the same but its not neccessary.I did it for piece of mind when I swapped my fluid out to the Schaeffers that I have been using in all my trucks.
 

quietpeen

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what the others have said about it being rated ATF +4 makes sense. i was thinking with synthetic vs. conventional when it comes to engine oil. I have always heard you can go from convention to synthetic, but once you make the switch it is bad to go back to convention. Wonder if the same applies for trans fluid.
 
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schroederMP

schroederMP

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Thanks for the info guys...I feel better now
 
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