How to get the chuck off a dcd950 dewalt hammer drill

There is a torx headed screw inside the chuck that is reverse thread (Right hand to loosen) - remove that then the chuck will spin off standard thread (Left hand loosen)
Most of the time I chuck a 1/2" allen wrench into the chuck, mount the drill in a vise, and strike the wrench with a hammer to get the chuck off

First check whether you have the correct transmission setting for the bit you are using. This may affect the range over which the chuck operates and how it locks onto the bit. A conventional small-diameter drill bit may not work with a hammer drill setting. If the setting is correct, then either your hands aren't as strong as they used to be and you're not getting the chuck tight, or the chuck is worn and no longer has enough friction to hold.

Try this diagnostic: when you put a bit in, use a fine-tip felt marker to draw a line from the chuck collar (the part you turn to tighten or loosen) to the chuck baseplate. If the bit comes loose, check to see if the collar is still lined up at the same place relative to the baseplate. If it is, the chuck pieces are slipping inside; perhaps the transmission setting is incorrect for the bit chosen. If the collar has worked loose (the marks didn't stay lined up), the threading on the collar or the parts it engages could be worn.

The DCD950 drill has a chuck that does not require the reverse-threaded lock screw. It is put on with lok-tite and a good deal of torque. It is hard to remove without the Dewalt vice tool to hold it but not impossible. Some can be removed by tightening the chuck in a vice and, using the drill handle for leverage, apply steady, even, strong pressure until it breaks free. Using this method usually bends the part of the chuck in the vice making it useless. Another reason for the chuck not turning when the motor is turning is a broken transmission. If the chuck works properly in tightening down and releasing bits, your problem may be in the transmission. If you go to http://www.ereplacementparts.com/ and search for your model number you can look at a breakdown of your drill and what you're looking at to replace the transmission.

Check the speed switch on top - sometimes it doesn't fully seat in the 1 or 2 position. Switch it to the opposite setting, run it, then switch back, until it seats properly. Also check the clutch control ring for the same issue.

if trying to remove the keyless chuck/open chuck and down inside is a hex screw useing a hex wrench place long end in screw and give the wrench a sharp rap with a hammer to break loose/....(not sure if dewalt has left or right hand threads)and i have had to rap a drill with a rag and place in vice to help hold it.......hope it helps

There is no loctite on the chuck threads, only blue loctite on the reverse screw. This is how I remove chucks.

Remove the REVERSE-THREAD screw at the bottom of the chuck. Set the clutch collar to the highest setting, and set the gear to the slowest setting on the transmission. Remove the power source! Get the biggest allen wrench you can fit in the end of the chuck(the shortest leg) and tighten the chuck down around it, allowing the jaws to rest and tighten on the flats of the wrench. Lay the drill on its side(chuck toward you, handle to the left, and allen wrench to the left, horizontal to the deck). Then with a hammer(soft hammer if you care about the allen wrench) quickly and deliberately hit the allen wrench in an attempt to cause the allen wrench to spin counter clockwise. Let me know if this works for you!

The dc925 and the current model dcd950 along with several other models of Dewalt 's line of cordless hammer drills DO NOT have a screw inside removal requires a CHUCK REMOVAL FIXTURE part #
233804-40 also you can't use a generic replacement chuck. As of 2/2/2010 the prices on the Dewaltservicenet web site are $72.74 for
the tool and $69.70 for the chuck, part # 330075-90.

Inside the chuck is a left-handed screw. torx (star) T20. When you get it out, take an allen wrench and (if you can tighten it up at all, tighten the **** out of it). If not, find an allen wrench, a tiny bit smaller than the space allowed. Now, get a nice big hammer. The chuck is right handed thread. And knock it, spinning the chuck off the spindle. May take a few whacks. Use the edge of a workbench to keep it stationery if need be. Please rate me

I just changed the chuck on my 18 volt xrp half inch hammer drill,yes first you must remove the torx screw with #15 torx bit,note this is a left handed thread screw,knowing the bad chuck was bad I added some heat from a propane torch to the chuck then making sure it was in 1st gear i took some vise grips and the chuck is screwed on with normal right handed threads,it broke loose (was stubborn but needs a lot of torque )ahhhhhh wat a pain.