Turns out it's the gearbox seal that failed, the thick gunge I took for engine oil was in fact old gearbox fluid, stuff just won't come out easily. Need to drive it more and do a change again further down the line. The filter should manage it all I'm the meantime as it works its way round
So ordered up a new seal for this week, shame on the delay as came out/apart really easily this time, us being experts now



This is what it should look like on one of my spare boxes, the steel sleeve comes off...somehow...from the input shaft, not just a simple push in like the manual box has or the original vw autobox
