</font><font color="blue" class="small">( Have been told the two cannot be mixed together. If they are, curdilling, or a non mix will happen, with bearing failure soon to happen. Anyone have any thoughts or better yet facts or publications on the subject?
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Personally..I wouldnt INTENTIONALLY mix them. What do you wind up with?? For a gear oil change Id just drain the "old" 90...and install the new stuff....I wouldnt worry about FLUSHING the old 90 out...but I sure wouldnt "pre-mix" the 2 into some sort of combo to install fresh.