Add Windshield Wiper / Washer Fluid: 1990 GMC S15 High Sierra 4.3L V6 Extended Cab Pickup

Adding windshield washer fluid to your 1990 GMC S15 is a fairly straightforward process. The video above shows you where the window washer fluid reservoir is located in your S15, how to remove the reservoir cap and how to refill the windshield wiper / washer fluid. The nice thing about adding windshield washer fluid is that you can't overfill the reservoir - once it's full, you can stop adding fluid!