I usually just do a full flush, videos for reference below but recently been experimenting with just how much improvement is there with just a drain and fill or in my case extraction and fill. After filling the transmission realized you can couple the two tubes
. Can feel the difference in smoothness and quietness in the 02 V70 XC 84K miles transmission. Will drive till perhaps the next oil change and do a full flush..
A 9 Liter is best for motor oil.
https://www.amazon.com/s?k=9+liter+flui ... nb_sb_noss
Should work well for fluid replenishing for both the front and rear transfer case.
https://www.amazon.com/s?k=200CC+Fluid+ ... nb_sb_noss
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