How much rotation is too much for a cv joint? I have a few degrees on my rear inners. What to know if that's too much before I degrease and boot them.

someone else with more knowledge may have a quantitative answer but, rear axles seem to be extremely robust and long-lasting. May have read of a failure once in over a decade of reading about Subarus across 2-3 Forums.

 

im not sure if i understand the question but if you looking at lifting the rig you can go 2" over stock with out issue any more than that and the cv joint pulls out of the cv cup i dont think the angle matters too mucb its more a traval issue

Maybe this will help - compare all of your axles in the same way (connected/not/inner joint/outer joint/etc) - if they all seem identical then what you're experiencing is probably normal.  If 3 are the same and one is notably different then you probably have an issue. 

I'm also unsure of what you're asking or describing or the "play".  CV's aren't fixed solid axle F150's and will have some "play" depending what you mean.  They can sort of "clink back and forth" normally if you're twisting and turning them...again depending what you mean - on the vehicle, off the vehicle, partially disassembled, is the trans in park, car off the ground, car on the ground, ebrake on...etc.