This is a 1987 GMC pickup and when it rains hard water drips from underneath my dash on the drivers side.It appears the drips are coming off the brake pedal rod thats going to the master cylinder.I hosed down the truck and still cant find the leak.When it rains there is no rain gettin on my brake master cylinder under the hood and the windshield seal is NOT bad.Perhaps the leak is coming from somewhere above the brake pedal rod that runs to the master cylinder.ANY help!!Wheres the water coming from??I will give a best answer on this one who has an idea where the leak is coming from!!Thanks.
Start with the windshield my friend ... Many times when it is replaced they never clean the old seal enough when setting the glass and you may have a leak at the top of your truck, or more likely at one of the corners ... the water likes to run down the window frame, under your dash and down the fire wall ... you may also have a weak spot in the bottom corner of your windshield under the glass ... either way it sounds like the water is coming from the windshield/window frame and considering the year and make of the truck I'd start with the windshield .. have you had it replaced before?
Many, many times I've replaced glass and found the old seal's where still there and rotten or poorly removed, allowing for a seal, but with many small openings that over time will allow water to get inside, sit and destroy the metal or at least weaken it and when looking for water problems, always start with the Windows and the seals around them.
Hope that helps.
1971 - 1972 DELUXE Windshield Rubber Seal Gasket Chevy GMC Truck, 1967 68 69 70 71 72 STANDARD Windshield Rubber Seal Gasket Chevy GMC Truck, 1960 61 62 63 STANDARD Windshield Rubber Seal Gasket Chevy GMC Truck, 1954 - 55 1st Series DELUXE Windshield Rubber Seal Gasket Chevy GMC Trucks, 1954 - 55 1sr Series STANDARD Windshield Rubber Seal Gasket Chevy GMC Trucks, Ford Truck Windshield w/ Trim & Rear Wrap Window Seals, 1953 1954 1955 Ford Pickup Truck Windshield Seal 53 54, Ford Closed Car Pickup Truck Rubber Windshield Seal Set, 1935 1936 Ford Closed Car Pickup Truck Windshield Seal, 1956 Ford Truck Windshield w/ Trim & Rear Window Seals, 1956 Ford Pickup Truck Windshield Seal '56 (for chrome), Ford Truck Windshield w/ Trim & Rear Window Seal Kit, 1951 1952 Ford Truck Windshield Seal w Groove for Trim, 1956 Ford Truck Windshield w/o Trim & Rear Window Seals, 1937 1938 1939 Ford Car & Truck Rubber Windshield Seal, Ford Truck Windshield without Trim & Rear Window Seals, 1953 - 1955 Ford Truck Windshield & Rear Window Seals, Ford Truck Windshield & Rear Wrap Around Window Seals, 1948 -1950 Ford Truck Windshield & Rear Window Seal Kit, 1956 Ford Pickup Truck Rubber Windshield Seal '56, 1948 - 1952 Ford Pickup Truck Windshield Seal 49 50 51, 35-36 Ford Pickup Comm Truck Closed Car Windshield Seal, NOS 1970's 1980's Dodge Truck Ramcharger D100 D200 Windshield Seal PN 3494298, Chevy GMC Truck windshield weatherstrip gasket - seal accepts trim 60 61 62 63, CHEVY GMC PICK UP TRUCK WINDSHIELD SEAL 55 56 57 58 59, 81 82 CHEVY LUV TRUCK WINDSHIELD SEAL ACCEPTS TRIM, 1981 1982 CHEVY LUV TRUCK WINDSHIELD SEAL, 1973 THRU 1987 CHEVY GMC TRUCK WINDSHIELD SEAL, 1972 THRU 1980 CHEVY LUV TRUCK WINDSHIELD SEAL, 1971 1972 Chevy GMC Truck windshield gasket weatherstrip seal 71 72, 1954 1955 1st SERIES CHEVY GMC TRUCK WINDSHIELD SEAL, 57 / 68 INTERNATIONAL PICKUP TRUCK WINDSHIELD SEAL, 79 THRU 86 DODGE D-50 TRUCK PICK-UP WINDSHIELD SEAL, 73/93 Dodge pick up truck windshield gasket weatherstrip seal and lock strip, 61 72 DODGE TRUCK PICK-UP WINDSHIELD SEAL & LOCK STRIP, 55 60 DODGE TRUCK PICK-UP WINDSHIELD SEAL & LOCK STRIP, FORD TRUCK PICK-UP WINDSHIELD SEAL 61 62 63 64 65 66, 77/79 FORD TRUCK PICK-UP WINDSHIELD SEAL WEATHERSTRIP, 77 78 79 FORD TRUCK PICK-UP WINDSHIELD SEAL WITH TRIM, 57 58 59 60 FORD TRUCK PICK-UP WINDSHIELD SEAL, NEW 1935 1936 Ford Pickup Truck & Closed Car Windshield Seal Weatherstrip , 1967 THRU 1977 FORD TRUCK PICK-UP WINDSHIELD SEAL, 1953 1954 1955 FORD TRUCK PICK-UP WINDSHIELD SEAL, 1948/1952 FORD TRUCK PICK-UP WINDSHIELD SEAL 49 50 51, 1948 1949 1950 1951 1952 Ford pick up truck windshield gasket seal weatherstrip, MAZDA B-SERIES PICK-UP TRUCK WINDSHIELD SEAL 1972/1985, DATSUN NISSAN 720 PICK-UP TRUCK WINDSHIELD SEAL 80 86, 79/83 TOYOTA PICK-UP TRUCK WINDSHIELD SEAL, 72 THRU 79 DATSUN 620 PICK-UP TRUCK WINDSHIELD SEAL, 72 THRU 78 TOYOTA PICK-UP TRUCK WINDSHIELD SEAL,
