2009 SILVERADO FRONT &BACK PASSENGER SIDE GET SOAKED UNDER CARPET

Rear washer is probably fed by a flexible tube from the front reservoir and pump and a soaked rear carpet indicates the tube has become detached from a fitting or has split.

Tube is typically difficult to access as they are often routed over the headlining or along the inner sill under the carpet or even inside the sill section.

The divider is generally not sealed at all, just a lump of metal reinforcement, the coolant may have pooled at the rear. The water will evaporate from the coolant mixture but the coolant will stay a long time so it'll have to be vacuumed out, add water and vacuum some more to pull it from the carpet and padding as much as possible. You can verify whether it's coolant or just rainwater by smelling the carpet. You may be nose blind to it by now from driving the car so have someone else sniff the carpet if you don't detect any coolant smell yourself. It'll also feel more slick than straight water if it's coolant so that's another way to ID the liquid. Option three is a cat or dog, they'll likely try to lick it if it's coolant but don't let it clean the carpet for you unless you dislike the animal.

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1) Check the pollen filter, its probably in a poor state if its not been changed yet.
2) Check the bulk head drains.
3) Check the sun roof drain pipes (usually run from under the sun roof, down the door pillars to the wheel arches, often covered by an plastic inner wing) clear out all the mud and debris.

If you've been using your air conditioner during this time, and it hasn't rained at all, then the small drain at the bottom of the a/c evaporator core may be plugged. When you use the a/c to cool the car the evaporator coil [located next to the heater core in the ductwork under the dash] is very cold and moisture from the hot humid air condenses on it as a result. This condensation dribbles down the core and accumulates in the plastic housing under it where it should then drain out a small hole and drip onto the ground. If the small drain gets plugged, which happens quite often, then the water fills up the housing until it overflows and then runs out and soaks the carpet on the front passenger side. The drain is located on the engine side of the firewall, passenger side, down low where the firewall begins to curve under. Usually a puff of air will clear the clog and the drain will work fine again. If the carpet is really wet it would be a good idea to remove it and get everything dry again as it tends to get pretty smelly if left wet. One last note: usually a leaky a/c unit will only make the passenger side carpet wet unless it's been leaking for a long time while a leaky windshield seal can make both sides wet depending on where it is leaking. Good luck, hope this helps you out!

the heater will not cause this. check under body for any damaged sheet metal. good test is go to carwash, give it a good soaking and see where it is leaking from.

I think that I can help you. It sounds like your drain-tube is plugged up. Get in the passenger side, and pull the carpet back from under the glove box. Look for a black rubber pipe that goes from a black box, and pokes thru the firewall, on the passenger side. Remove the hose from the box, and have a container ready to catch water. If water comes out of the black box, your drain hose is plugged up. Clean out the clog, and you will be golden.

check your condensation drip tube on passenger of firewall it is most likely clogged with sand preventing the water from draining out

look at the firewall on the engine side and you will see a small stub hose coming out on passenger side about even with the bottom of the heater box inside. that hose drains condensation from the ac...clear it out and you will have a dry floor. (unless heater core is leaking but you didn't mention any overheat or coolant loss so likely that's not a problem)

try draining the evaporator box.. u can have a shop lift the vehicle and blow compressed air up the evaporator drain tube from under the vehicle..the tube is under the car from the area of the passenger floor...it should pour out almost immediatelt after shooting compressed air up the tube ...stand back if doin it urself..or u will take a shower...sounds like u have a clogged evaporator drain

You need to go under the vehicle and unplug the rubber drain for the a/c.The drain can somtimes be reached under the hood on the passenger side fire wall.