On a Mk1 850, its jumping out of 3rd gear. Its fine when youre at a constant speed but when you decelerate the gear stick drops and it pops out of gear.
I have fitted a bottom engine steady thinking it was the engine moving around buts its still the same. Not sure if there is any merit replacing the top steady rubbers and what ever it takes to hold the engine solid. Also wondered if there is anything else externally that can cause this?
But I suspect its a case of taking the engine out and getting the gear box looked at?