I think the problem for the Espirt is that the gearbox comes from the Renault 25, which was discontinued a long time ago and renault are now running out of them. Becasue Lotus sells so few Esprits it is not economic to design and build and new gear box. I'm not sure why they can't just buy a newer gear box from another manuafcturer though, maybe limited space in the Espirt? Apparently the gear box is the worst bit of the car so it would be great if they could find an alternetive source.