1993 GMC Rally Wagon 3500 Repair and Maintenance
A guide to problems, costs, maintenance and repair for your 1993 GMC Rally Wagon 3500
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1993 GMC Rally Wagon 3500 ProblemsFlush brake fluid every 60,000 miles
Our technicians highly recommend that the transmission is serviced every 30,000 miles to avoid problems and maintain optimal operating order. As for the 4L80-E Transmission (Diesel adn 7.4L gas engine), Transmission fluid may leak through the electrical connector on the side of the transmission, damaging the wire harness and causing the transmission to shift erratically. Our technicians tell us there are updated shift solenoids, an internal transmission harness, and a connector pigtail available to correct this fault.
An engine vacuum leak may develop from the throttle body gasket causing a higher than normal idle speed. Failed gaskets should be replaced.