2011 sd4

Morning all,
Have had my 2011 sd4 nearly a year now. Love the car, but after a while had a bit of a judder in 1st pulling off and reverse. No issues in command shift. Yesterday pulling off car felt like it was about to stall and foot went to the floor and no power. Then all of a sudden like a rocket pulling off. I've been told.maybe an update on gearbox will help which is booked in Friday with a diagnostic. Recently had a haldex service anyone had or going through similar?
Cheers

Does it also it when going round corners? If so it's an issue with the Haldex. It's grabbing when it shouldn't be, which can be caused by several issues within the unit itself.

Hi Davey.
Do let us know the outcome of the diagnostic check, are you say it was not doing this until you had the Haldex serviced, if so it must have something to do with that?