G'day Wes,
That is great information and should help others.

I have a Victa 4215HX 1998 model, it is powered by a 15hp Tecumseh engine.
I researched changing the oil in the transaxle and found this success story, which I will attach.
http://peerless205-024c.blogspot.com.au/2013/07/how-i-solved-my-sluggish-murray-riding.html

Numbers can be found on the axle.
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Mine was full of grass & dirt on top, in between the fins. The design of it really catches the dirt and grass well, helping it over heat.

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Pic's from the success story.

Some oils that I have found people have used.
Valvoline full synthetic 20W-50 motorcycle oil
Lucas all-purpose hydraulic fluid

My mower drives slow (acceptable speed) I think it should be faster, not sure, I have nothing to compare it to.
Climbs OK, I believe it should be better.



Happy is he who penetrates the mystery of things.