I really wanted to like this drill.  It seems to be tough and powerful.  And it is.  However, as I was drilling a particularly tough hole two things happened: first, I noticed a loss of power and a hard clicking sound.  Second, after immediately stopping and unplugging the drill I noticed the chuck had come loose.  I am not a weak chucker, so I was very surprised it had loosened.  My hope is that the loss of power and the noise was a direct correlation of the loose chuck.  This was not the case.

I have contacted Hitachi for further instructions, but I will probably be moving over to a different brand of drill.  This one had some serious power, but apparently has more than a few structural flaws.
I really wanted to like this drill. It seems to be tough and powerful. And it is. However, as I was drilling a particularly tough hole two things happened: first, I noticed a loss of power and a hard clicking sound. Second, after immediately stopping and unplugging the drill I noticed the chuck had come loose. I am not a weak chucker, so I was very surprised it had loosened. My hope is that the loss of power and the noise was a direct correlation of the loose chuck. This was not the case. I have contacted Hitachi for further instructions, but I will probably be moving over to a different brand of drill. This one had some serious power, but apparently has more than a few structural flaws.