Last Fall just used my last old stash Quart of Defy with Slick 50 (10w30) in the Tecumseh Snowblower.
One of the best oils I ever used.
I would just mix it with some Formula Shell or QSGB.
Zinc gets used up under high stress, so the Defy SL its just starting 50% higher treat rate than current. When you run the oil hard you will use up that zdp. Its still shows in a UOA but its used and converted.
You may also use Castrol Motorcyle 4T "Dino" which will have more zinc than defy. That is AP SH rated due to high Phosphorous from the ZDP treat rate.
2014 Nissan Rogue S CVT, OC#9 41392mi-QSUD10W30 + M110A CHAMP Filter; 2017 Subaru Crosstrek CVT OC#2 ?? mi-SOA/Idemitsu 0w20 + SOA Filter