Unable to remove chuck from cordless drill

I have a DDF453 cordless drill and the chuck has been playing up so ordered a replacement. While waiting for it to arrive I thought Id remove the old chuck. Found a useful YouTube and removed the LH thread internal screw inside the chuck and tried to unscrew the chuck body which should be RH thread. No joy. Various wrenches and tecniques used, none effective. I am now in the process of trying to cut the chuck off with an angle grinder, at every stage trying to unwind it. Still no joy.

Any advice please, people?

Thanks,

Pete

I had the same problem, in my Ddf486 the chuck was glued with hard red loctite, no chance to undo, I smashed on an Allen key secured in the chick and Bent a bit everything.

 

the only solution is grind with a lot of caution to not damage the thread or di mantle completely and when you have the shaft on hands you can try to warm with flame and try to remove. 
 

Not a happy journey anyway..