Tony,
Andy is right here, you may not have a terminal problem.
From what you say, you are experiencing shock when shifts are made. What shifts? On every gearchange, or only on a particular range?
Troubleshooting guide suggests the following possible causes:
Faulty control unit
Valve sticking
Faulty accumulator
Deterioration of ATF
Of which the valve and accumulators are in the sump, don't need the box taken out.
Also suggests checking over-running clutch, high clutch [for slippage] and for band and servo slippage. These last ones
are inside the tranny.
Try describing what is happening on the Technical forum, you get a lot of sensible answers from the guys.
Hope it is not too serious.
Joe
BTW, there is a specialist crew in Glasgow who do all Subaru trannies. They will rebuild yours for c.£1800 if memory serves me right. This is not a major expense relatively speaking, they know the boxes and will do a good job.
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