I'm getting a knocking from rear and a wobble when I do hard slow turn i checked the rear drive shafts drivers side seems fine but I can pull other side backwards and forwards a couple inches from hub back to diff is this normal

 

I had a similar problem on my old Impreza front drive shaft,the spring pin was missing so had a lot of movement.

 

Did you have to replace whole shaft, I was thinking if I could do axle nut up maybe it's come loose

 

No I just knocked a new pin in there.

 

Don't suppose you know where I get one from for a newage

 

I just used a standard spring pin from my toolbox,can't remember the size tho,was something like this one:
http://importcarparts.co.uk/parts-info.asp?id=7627

Not sure if rear is the same tho?
Have you checked to see if it is a missing/snapped pin?

 

There are no roll pins for the rear drive shafts, as far as I know. The shafts are secured with one of these circlips:

http://parts.subaru.com/p/Subaru__/CIRCLIP-NO1/49237112/28033FA000.html

Not sure who else does mail order of these things, but I'd try alyn at ASAP Performance.

 

Ok thanks il have a look tomorrow to see if it's missing , do you just hammer them in then

 

Would that cause it to have a bit of movement