2004 1500 base model 256,000m

Slowly working through a bunch of issues with this vehicle. Replaced all the window washer tubing and spray nozzles. [were all cracked]. working fine. Overnight there is a wet patch on the ground, and blue liquid on the base of the reservoir. Removed it, but pressurizing [blowing] shows no leaks. Its irritating as hell.

 

Is the pump built into the reservoir? I have had leaky pumps before doing what you describe

 

I have a 2004 2500 HD pick-up and had the same issue you're having, except mine was leaking washer fluid onto the floor. Because the windshield washer pump is mounted at the bottom of the reservoir, there is a smal grommet that seals the pump into the reservoir. I fixed mine by replacing that grommet. No more leaks

 

I have a 2006 Silverado and I can fill the reservoir, and it will hold liquid for weeks. If I *USE* it a single time, it then leaks out within a day. I initially thought it was the reservoir, but have determined the pump itself is leaking, and until you prime the pump by running it, the reservoir holds washer fluid. I've just been too lazy to figure out how to access it, as I cannot easily reach the bottom of the thing.

Anyway, I will bet yours is also the cheap little pump.

 

YESS I removed and filled the reservoir with water, and no leaks.Set it on the counter for a while, and it leaked. The pump is leaking if its tilted. WTF. new pump arrived off Amazon, had to file down the connector housing to get it connected, but its finally good. Had to take out battery, remove battery battery pan [maybe not necessary] and pull the whole tank from under.

 

Thanks for confirming what I figured I would have to do - i.e. remove the battery and battery pan. That's why I've been lazy, and I just don't bother filling my washer fluid reservoir most of the time. I keep a jug of it in the toolbox in the back of the truck, and pour a bit in there if I am dealing with lots of bugs hitting the windshield, etc, knowing it will leak out within a day. I've got replacing the pump on my to-do list.