My 2.7D 130miles XF is going into limp mode and "gearbox error" shows on the dash. Restart solves the problem and driving in sport mode causes no issue.

When in D the car will stutter and then the gearbox error will appear. If driven very carefully the issue won't happen.

New battery and good terminals so I don't think it's voltage related.

See below codes from diagnostics:

U0100
U0101
U0121
U0155
U0423

Is it repairable or will she be sent to the scrap yard!! Car has been serviced regularly etc but I myself haven't changed the gearbox oil in the few years I've owned it.

Thanks

 

Kind of lost here?
What gear box errors? You only post U codes which are network related codes. They most likely are transient or battery related? They are labeled as historic so I think they are old and out of date codes?

First clear the codes and see what comes back. Note you will always have a P1000 or a P1111 code to indicated the status of the readiness monitors and I see neither code?
Good that you have replaced the battery. What is the voltage of the battery after the car has sat over night?
Consider at least checking the fluid level in the transmission. With those miles your over due for a transmission service too. Also be aware that a low fluid level can cause all this?
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