how do you get the chuck off once the screw is out

Hi Rob,Well that the million dollar questions.Both Dewalt and Ereplacementparts have instructions and video's on how to remove chucks. I never had much luck removing a chuck buy tightening a allen wrench in the chuck and then hitting it smartly with a hammer. We remove and replace a lot of chucks in our shop and we have a 1/2" socket adapter that we clamp into the chuck and then put a 1/2" impact on it to take it off.That works most of the time unless the chuck is broken. If the chuck is broken we take a 1/2" screw extractor and hammer it tightly in the nose and use a square drive scoket on the impact to remove it.
Now if that doesn't work we clamp the chuck and drill in a vise and take a high speed cut off wheel and split the chuck like a banana then take a air chisel stick the bit in the cut and open it enough to screw off the chuck.
If that won't work then Ive been known to take the drill out side and throw it up on the roof.
So what I'm trying to say is all chuck are different,some are easy and other are almost impossible to get off. I don't know if this helps but its a place to start.Good luck
Tinker

Turn the chuck all the way open and look inside where the drill bit inserts. There should be a Torx head screw you need to remove. Be very careful because this screw has reverse threads and also lock tite on the threads. It may require a quality torx bit to get it popped loose. Do not forget the reverse threads. Turn the screw clockwise to loosen the torx screw. Hope this helps, Courtney W.

hello! start by checking the brush and holder assembly check the connection lead at the brush holder these types have a tendency to burn out the connector tab on the brush holder. if all those parts are good then i'm sad to say yo need a new motor. good luck!

Hey brando,
Not a diagram or schematic that I am aware of..[I tried to get a Dewalt service center to help me reassemble a transmission once..they gave me a wink,wink..and a head nod...and sold me a new one..]
I was able to reassemble one at a later date..but it is just a trial and error method..not one for the faint of heart..:)
Part # 397892-05 avail at ereplacementparts.com
hope this helps..?
Craig

Hey caseys,
usually it is the transmission that is bad [slipping] and not the gearbox..[it may seem like the gearbox..!] sorry but you will have to change out the transmission to repair you problem..
Hope this has been helpful..
Craig
Geneva Tool Repair

Chuck, I replaced the transmission, ( inexpensive part ) and the drill now works fine at all levels

THANK YOU

Are you trying to reassemble a cordless drill transmission? Once those things come apart it's interesting to get them back together. :) Still, I'll see what I can find for you.

On these cordless drills, it can be tough to get a parts breakdown for the transmission itself. The reason is that most manufacturers usually offer the transmission as a whole part (see figure 11 on the diagram - the link to the diagram is at the bottom of this page).

The individual pieces inside the transmission are not available for purchase. The price on the transmission is not too bad however, it is about $39.00. In many cases it will be worth it to buy a new transmission to fix the drill. The transmission can be found here:

397892-05 Transmission - $39.95

Hope this helps.

For sure, every brand has its gremlins. Personally I haven't heard of more problems with Dewalt cordless tools over other brands. Over time any switch will wear out, but as for the motor, I do hear of a lot of people overworking their cordless drills (mixing mud, running 3" hole saws etc) which can cause a lot of problems. That may or may not have happened here. Of course Dewalt doesn't make their cordless drill chucks, but if I remember correctly that Jacobs chuck on the DW988 wasn't the best. Their new Rohm chuck is pretty impressive though.