DeWalt 12V cordless the chuck mow backs out under load

The charger for the dewalt 18V battery.
http://www.ezbuybatteries.com/dewalt-72v-18v-battery-charger-universal-replacement-13821.html

In the past when this has happened to me I have had to replace the chuck. Problem is, the chuck is not a normal one and the correct chuck has a list price of about 65 pound and needs a special service tool to take it off and put it on again.

I answered that question already on another post, but if you need to know how to remove the chuck I have detailed instructions in the TIP SECTION on how to do this. Let me know if you need more help

Inside the chuck, if it is wide open, you should see a screw with a T20 head It is reverse thread so turn to the right to loosen. If it is too tight, clamp gently with the chuck facing up and let some WD-40 soak in for a while.

If you open the chuck all the way you will see a Allen wrench screw down the throat. If you can get that off you will beable to pull the hole chuck off. Turn the chuck so you can see the bottom and you should see the cruves where you can slide it back in.

open the chuck fully and it shoudl have a screw inside. Unscrew it, but be carefull, these screws are usually reversed - to uncsrew, rotate it clockwise. Once done, put allen key into chuck (short side in), fasten the chuck to hold allen key well and hit the key with hammer - counterclockwise direction. You might want to verify this procedure with someone else as I have no experience with Dewalt, but this way it works for Makita, Metabo, Narex, ... then why not for Dewalt? Juraj

Hi there, Remove the battery and sometimes the screws on the drill casing are a torx instead of phillips so you will need a set of torx screwdrivers. Once you have removed the screws from the casing be very carefull when pulling the two casings apart, try to leave the chuck, motor and switch assembly in one half of the casing as it makes it much easier when trying to put it back together.

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.

grasp the chuck and put drill in reverse position and pull trigger gently this will open chuck and re-insert bit do same in forward to tighten bit into chuck

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.