Chevrolet Repair: water in pickup cab, core leak, pickup cab

Question
This winter my 1998 k-1500 Silverado started leaking water on
the passenger side floor. No recent windshield work or repairs. It
isn't coolant, I suspected heater core leak, and only occurs when
it rains. I haven't removed underside of dash thinking the
problem may be accessible from the outside. Any suggestions as
to where to start looking?

Answer
Hi Mic, To start I would remove the panel under the wiper blades and look for a sheild that might stop water from going into the air inlet for the blower motor. I haven't had a leak on a pick up but have seen it on the Impala and Monte Carlo. If all looks good in there use a garden hose with nothing on the hose (sprayer) and run water around the cowl panel while someone is inside looking for the leak.

Hope this helps you

Mark