One problem related to brake drum wheel cylinder has been reported for the 1998 Plymouth Grand Voyager. The most recently reported issues are listed below.
My local automotive repair shop told me I had brake fluid leakage on my rear brakes; I took the vehicle back to the dealership and sure enough they replaced the the wheel cylinders in the rear. The van had only 11,000 miles. It was by chance this was caught, I was having the tires balanced and rotated.