Sorry for silly question, but have to drop son of at University tomorrow and with Damage to Gearbox I don't have the higher gears. Is it safe to drive/cruise in that gear for that duration, I plan on doing it in two stages (might stay over) 

Ford will have specified a maximum continuous engine speed as well as a maximum intermittent one. I don't know exactly what they are for your engine but they are likely to be over 5500 rpm. If you are doing the journey at speed then it would be advisable to keep a close eye on the coolant temperature.

That does not mean that your gearbox isn't going to fall to bits depending on what the problem with it is.

4th Gear will be okay for that length of journey for a normal gearbox so be careful with your damaged one. You are more at risk of spending 100's of fuel than the gear going. As Tizer said tho, keep an eye on engine temp as a long journey in a lower gear will make it warm 😉

On the plus side, keeping revs that high for that period of time will do a good job at cleaning the injectors out! (assuming it is a petrol engine)

With a good box, yes, in your case, no. There is obviously damage within the gearbox. You would have to be irredeemably stupid even to try it. The box may be repairable at the moment but if it breaks big time it will be a tow home if not an accident and you definitely won't get any goodwill from Ford . Hire a car for the day.

10 minutes ago, anon said:

With a good box, yes, in your case, no. There is obviously damage within the gearbox. You would have to be irredeemably stupid even to try it. The box may be repairable at the moment but if it breaks big time it will be a tow home if not an accident and you definitely won't get any goodwill from Ford . Hire a car for the day.

Thanks again. I was all willing to try it until your response, I'm going to have to use the car for work later in the week, where I could be deployed up to 40 miles away but now am worried about that even!  I'll use my partners car tomorrow, an 09 FF that's been more reliable than my car! 

Supposing that the damage has broken something inside the box. If the bit that is broken jams between two gears, the forces involved will shatter the gearbox casing so I applaud your decision to use another car.

You will find it far less stressful to use another car. I recently had a fault warning on my Fiesta while in Germany, so I had to drive home to a neighbouring country in limp home mode. It is just not worth the stress and risk of something going more wrong if you can avoid it.