I have read several items on the net about replacing clear DRL bulbs in 2004-2007 Silvers with Amber bulbs and also LED bulbs. One account indicated that the 4114 stock bulb is made for 14 volts and the 3157 Amber is made for 12, so the 3157 won't survive. I don't buy into this. All of the bulbs in the truck have to be able to take 14-15 volts occasionally and at least 13.5 all the time, unless it;s one that specifically has a regulator circuit for some reason. I have had 3157 Amber in my DRL's for over 2 years....no burnout, no overheat, nothing. Socket is not damaged either. If anything the 4114 bulb spec is probably 16 volts so that it does not run "at capacity" all the time. I know the 3157 works to same brightness as my flashers, so it is not being overdriven. For LED's, I have read where guys are putting a 1/2 watt, 15 Ohm resistor in series with the socket to reduce voltage by 1.5 to 2 volts and keep LED's at 11.5 -12 so they don't burn out. If you buy a good LED with a regulator built in, they should be fine. I am going to try a set soon, but I know others that have and they work fine. Initally everyone said LED's won't work in the DRL circuit, but I don't think the circuit was the problem. On my 2000 S10 Xtreme (wish I still owned) I turned off the DRL circuit that drove the high beams at 3/4 voltage because those suck. Instead I installed a set of sockets on the inner portion of the font marker light lense on each side where GM put socket holes, but no light. There is only one on the outside part. I put 912 bulbs in those and intially put them on the Ign for DRLs, but later changed them to 194's and ran them with the parking lights to light up the whole lense like GM should have to begin with. Also, if you need a good rear end warning light to compliment your 4-ways for those occaisional roadside stops to chaneg an old lady's tire.....convert your cargo light to a alternating flasher. You simply seperate the bulbs leads and install a alternating flasher (Federal Signal) powered by the lead from the switch. Alternating white lights up high like that get more attention that the red ones blinking on the back. You need all the help you can get now days, people drive like maniacs and are only concerned with themselves, thier phone and iPod.