Lately I've been getting water in both the driver's and passenger's side floor. It doesn't appear to be linked to washing the truck or the rain, and it certainly isn't coolant. The firewall is dry on the inside of the cab, and there's never a large amount of water, just enough to make things damp. I can't tell if the floor is wet until i pull my floormats back. Where on earth could it be coming in from?

 

A/C evaporator has a drip tray, and a drain hose that runs down passenger side of center floor hump, if hose gets clogged tray can slosh water out either side.
A/C runs with A/C on of course, but also when Defrost is on

Cab brake light gasket leak can make front wet on either side

Usually windshield corner leak will only be 1 corner so only one side will be wet
At the bottom of the windshield, under the trim, is a trough that collects water, it can rust through at the corners, but dry firewall would mean that probably hasn't happened

 

I'll give the AC line a look first. Thanks Ron!

 

spent about 20 minutes looking around; and I'm curious as to where this drip tray lives? In the dash somewhere?

 

Inside the cab between glove box and center of dash

Look at this video: www.youtube.com/watch?v=vh-bI3ZdRoA

On some models if you pull back carpet on passenger side center hump you will see a drain hose running down and out floor pan

Depends on year and model

 

Yeah, found that port on the firewall. Took the chance to blow some compressed air through there and it was free flowing. No water or gunk came out, so I'm thinking that isn't my issue, but next time I'm out, I'll crank on the A/C and take a look for the water.

Certainly explains what that black box is in the footwell, lol

 

OK, something peculiar.

Drove round today with the AC on full blast the entire time. Came home and that drain/weep hole was bone dry. Floors were dry before I left, now they're wet. Didn't rain, didn't wash my truck between then and now.

I find this odd because the tube doesn't seem to be plugged, but it clearly is. Any advice on how to proceed from here, now that I believe I've without a doubt proven where the water is coming from?

 

You are right, even after a short time that drain should be dripping water.

What year is the Ranger?

Google: "year" Ranger evaporator replacement

Not that you need to replace it, just trying to get diagrams of the layout and drain setup

 

It's a 1999 with the 3.0 V6.

Thanks, I'll take a quick search at that.