I am wanting to flush the radiator and cannot locate the drain for the radiator. Forgot to mention it's a 2004 S15 6 cylinder 4 x4

 

It may vary depending on your year so this may not pertain to you but on my '02 it is located on the bottom left side of the radiator (if you're looking at the car). Use a 1/4 square key to turn the drain ****. Its a P.I.T.A to get to so you'll need a universal. Hope this helps.

 

or you can do it the lazy way and just remove the lower hose

 

I actually had a hard time locating mine at first. To flush the system I disconnected one of the hoses to the heater core and put a 5' piece of clear tubing in its place and ran that along side the car. I then stuck a garden hose in the radiator and let the engine cycle the fresh water for about 5 min. It's a great way to ensure you get all the Death-cool out. Its not the best method for catching all the old coolant as it comes out rather quickly once you start the engine (sorry EPA).

 

The petcock is on the passenger side, underneath the lower radiator hose. 1/4" ratchet will unscrew it. Do a quick search for "petcock" to find out some other issues.

 

Not all of the 2004 S-10 Blazers w/4/3 V6 have a petcock. On the lower right corner of mine, (passenger-side) there is a 1 1/2" black plastic tube, about 1/2" in diameter. It has a small black tube coming off the side but with no attachments, white plastic, etc. It's actually easy to access, but when you look into the tube with an inspection mirror, there's nothing in the tube. It's blank, round, and sealed off. (Looks like a cigarette snuffer!) On the driver's side, at the lower corner, there's only a fitting with a metal tube coming out of it, which is some other type of fluid that's routed there for cooling. The lower radiator hose, which is mounted on the passenger side, is actually about 6" ABOVE the bottom of the radiator, which doesn't make for easy flushing. I guess I could totally remove the radiator so I can turn it upside down to flush it, or is there a kit available to install a petcock valve in the small, black, blank tube, located where the petcock should be?

 

I was just curious if you ever got a good answer to where you're supposed to drain your coolant from, when the radiator doesn't have a petcock valve.

 

Is there an answer to this question I cant seem to find the drain on mine. its exactly as decribed abovre. I know this is an old thread but its the only thing that comes up in the search

 

PS lower corner, on most there is a (probably dirty) off-white plastic plug that 90% of them have the "ears" of it broken off. If the ears are broken it can be a PITA to remove.
Take a look in that area & see what you have. If the ears are broken, then get a new one before removing the old one.
Just had another thought: Google your year etc for a radiator in Images on Google.
Hopefully there will be some pics showing what is what on your rad.

 

The last time I drained mine it was on the passenger side bottom but it wouldn't drain worth a crap. I think it was gunked up with dirt and what not. I ended up pulling the lower rad hose off the bottom of the rad. Honestly it is way easier, messy, but easier. If your ride has a bunch of miles on it I wouldn't be confident it wouldn't break as you're trying to loosen it being old plastic and all.