Coolant leaking through drip pan??

Hi guys,
It's been a long time! My 2004 Avalanche is still alive and kicking. All of a sudden I have been losing coolant, and slowly over heating. I have always been able to pull over, cool down and add more coolant. Obviously this can't be a long term strategy, so I'm hoping for some help...

The coolant seems to be dripping down underneath the truck, through the drip pan. I took some pictures, but don't know how helpful they are. It was night time, but it looks like it's dripping from the the hole in the drip pan, on the passengers side (there appears to be two holes or openings.

I don't know where the leak is originating from. I'm hopeful to fix this on my own.
Any guidance is appreciated.
Thank you,

Ok. Evidently I can?t upload pics from my iPhone. I?ll tey this link for the time being...
https://www15.online-convert.com/dl/web2/download-file/a94c5695-4427-4623-b1be-fbc5067d5c20/58337B5F-3C6F-4ADB-A0C9-7F8E3973B367.jpg

https://www15.online-convert.com/dl/web2/download-file/de52dad1-ed27-47eb-a9c0-d8bcb41d4bdd/F115DC52-6084-48D5-B18D-A8BE899AA66E.jpg

Water Pump maybe

Need to remove pan and inspect or look from top.
GEt a pressure tester and you can find leak while cold which is much easier.

Could be water pump or anyone of the hoses or radiator or block freeze plug

I thank you to all of the replies, I appreciate it. One thing to note, it will hold coolant while running and maintain temp. After the truck is shut off and cooled (hours), it does a slow drip. I don?t know if that means anything specific.
Thanks,

It is likely one of three things.. Water pump, hoses or radiator. That cover you are talking about is likely the "armor platting" that comes stock on a Z71 to protect the bottom of the engine compartment from debris when going off road. Coolant leaking from above will catch on that plate and dribble out of the drain holes.

With hose or radiator you would likely have a constant leak until the coolant drops below the leaking point when off or continually when running.

Water pump has a weep hole that leaks when the bearings are going out. Most likely that weep hole based on your observations which then requires replacement of the water pump. Note if you replace the water pump yourself that there are two sizes of thermostats so you will want to bring your water pump with you to the store to compare to one your getting. As far as I know I haven't heard why there are two different sized thermostats so if you can't find the right pump you SHOULD be able to just replace it with the other as long as you get a new thermostat housing and thermostat to match.

Good luck! You can likely pull off the plastic cowl around your coolant fan and check for where the coolant is coming from.

If you are overheating then loosing coolant then you might have a bad fan clutch assuming you have mechanical fan.

Very good post by redheadedrod. I had a bad waterpump gasket causing a slow leak, but I never saw it drip. The key here is that there is no fluid loss while running. What is the engine temp while driving? Mine runs right about 190 and I have the electric fan mod. It still stayed there even when I had the original clutch fan. 2004 is the year I believe they started using factory electric fans, but I could be wrong. I do know that when running, the wind over the radiator is enough that the fans do not engage; they are only used while idling. So could be the fan or more than one problem.

phatdrew said:

I thank you to all of the replies, I appreciate it. One thing to note, it will hold coolant while running and maintain temp. After the truck is shut off and cooled (hours), it does a slow drip. I don?t know if that means anything specific.
Thanks,

Click to expand...

My 03 would loose coolant overnight, but I could drive it to work and while sitting there 8.5 hours it didn't leak.  Changing the water pump took care of it.