Hi Martin, I was more wondering why you started looking at it, was it leaking oil, not going into gear, no drive at all?
We had a 35 year old PRM 220 gearbox on an Isuzu 38. Very solid, hydraulic gear box, not made any more. The output bearing was worn, so it was hard to get engine alignment, consequently we found it was leaking oil, but that wasn't apparent at the time. I had 'experts' look over the whole engine and gearbox (we ended up replacing the whole lot with a new Beta 35). And we got the gearbox upgraded from the standard spec to the modern equivalent of the old gearbox, still by