Here's how you want to set Daylight savings time in the US. If you haven't done so already, I'm sure your logs may be a little out of wack. Remember to add your correct time-zone to this, as I'm using Eastern.
Router(config)# clock timezone EST -5
Router(config)# clock summer-time EDT recurring 2 Sunday March 02:00 1 Sunday November 02:00 60
Now, let's explain. What you are doing here is starting by telling your device that you want to set your normal time-zone as Eastern Standard Time with an offset from UTC as -5 Hours. Then you're going to configure "summer-time" or daylight savings time. "EDT" is the word used for Eastern Daylight Time. I'm setting it as "recurring" as we have it every year. Then I'm telling it to start on the 2nd Sunday of March at 2:00 AM and to end on the 1st Sunday of November at 2:00 AM with a 60 Minute offset. The US Navy says that these are the proper dates (click here for proof).
While we're at it, let's make sure that our clock is correct. Here's 2 NTP servers I like to add to my configs:
Router(config)# ntp server 188.8.131.52
Router(config)# ntp server 184.108.40.206
The DNS names for these servers are 0.north-america.pool.ntp.org and 1.north-america.pool.ntp.org. You can be pretty sure that they are going to be correct.