Sierra Denali Marking It’s Territory

Thought I got a sniff of coolant last night when I got home but took a second and third sniff around the hood and nothing.  Tonight drive home with no issues park as normal.  Come out an hour later and find about a half gallon of coolant on the ground. Searching around and it does not look like it is any of the hoses. As best I can see the water pump looks ok. The one or two small drips I could see look like they are coming from the passenger side of the RAD.  

So any tricks for rad replacement in a 03 Sierra Denali?  It has both a trans and an oil cooler in it. I will probably do all the hoses and the belts while I am there. Any other while you’re are there parts? 

T stat?

Before you start, check to see if your truck actually has a drain plug in the radiator. I wasted a lot of time trying to remove one that did not exist on my 05 Tahoe.  Couldn't get an eyeball on the spot, but could feel what I thought was the drain plug.  Apparently GM eliminated them (at least in trucks & SUVs) for a few years in that time period but still molded the bung location and a small protrusion. 

My water pump went at about 150k miles. I just did an entire system replacement at that point. New water pump, t-stat, radiator, hoses, coolant, & pressure cap on the overflow tank. I think it was about $350-$400 in parts.

And it is the water pump.