Repairs 2011 rzt 50

I went to add 20w-50 to the rear axles.But noticed the old fluid had more of a red tint.I'm guessing it's a transmission type fluid.I added just a little probably not even a 1/4 of a quart is it okay to mix them.Or should I drain it and replace with only one kind.Also which do you'll recommend,and do you have to purge this model thanks.model:17WI2ACP056

see pages 30 & 31 in manuals. you will need your model & serial numbers.