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Discussion Starter #1
I noticed this leak yesterday evening about an hour after I parked in my driveway. I went outside to take the garbage out and noticed a wet spot about 12" in diameter on the driveway almost perfectly centered under the engine. It was dark so I took a flashlight and noticed a coolant dripping constantly (a drop every 10 seconds or so) but couldn't get too good of a look last night to try to trace it. I crawled under and peeked up and it does seem to be trickling down from the water pump area, but I couldn't get a good view of anything that might be the source (up higher, weep hole, etc), just a trail of coolant. The vehicle sat overnight and when I came out this morning to get in (after sitting for 14 hours) the wet spot was still there, but not quite as large in diameter (maybe 6-8"), but I could tell there were still very fresh drips. Before I go tearing into it trying to track down the source, hopefully I can eliminate and narrow down a few things with this post. Will the water pump still leak after the engine is shut off? Mine was replaced about 5 years ago as an FYI. What else could be the possible culprit for constantly dripping even after the engine is shut off? I haven't gotten a low coolant level message yet but plan on picking up a few gallons of 50/50 today until I figure out the problem.

The 'T' connector on my heater core was leaking in the winter when I ran the heat, but the wet spot it created was in a different area on the ground. I haven't gotten around to replacing the 'T' connector yet. I also noticed I no longer have front heat. Not that I need it in July, but on a road trip this past weekend I tried adjusting my A/C temp up from 60 to 72-74 and noticed no difference, so I turned the compressor off and cranked it to 90 and let it run for a few minutes and it was just fresh air. Not sure if its related at all, just throwing it out there.

Thanks for any info.
 

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My suggestion is find a friend that has a coolant pressure tester, or borrow one from autozone, and with the engine cold, pressure it up to about 10-15psi. You should be able to identify where it is coming from without burning yourself. The pressure will simulate the pressure buildup when the engine is hot and running. That is generally how I start diagnosing coolant leaks.
 

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Discussion Starter #3
I parked it when I got home from work last night and checked it a few hours later and the ground was bone dry. I cranked the engine up and backed up about 5 feet to get in good light, the engine wasn't running more than 10 seconds... I crawl underneath with a good flashlight and sure enough a slow and steady stream starts coming from the weep hole. I'm going to swap it out tonight or tomorrow, doesn't look that bad of a job but what about draining/replacing the coolant? The pump was replaced about 5 years ago and I had a coolant flush done at the same time and ditched the dexcool so I have the regular 'green' coolant now. How much will drain and how much needs to be replaced? Just need to know how much to buy... thanks.
 

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ur manual should tell u how much u need...gotta help urself a little bit too. my buddy google is a know it all as well
 

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I would get 3-4 gallons to be safe. I think capacity is somewhere around 14 qts bone dry, you could always bring one back or whatever. Draining it sucks without making a mess. I drained mine from the water pump and used a funnel with a hose down to under the truck. I tried to drain it as slow as possible to not make too much of a mess.
 

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I would probably get 2 gallons, maybe three. Make sure if you buy straight antifreeze to mix it 50/50 with water. Water is actually what provides the thermal properties needed to cool an engine. The reason the water does not boil when the temperature reaches 212* is because the system is pressurized along with the glycol, and it raises the boiling point. Here in Texas, I typically mix a 70/30 heavier on water when working on coolant systems.
 
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