93 Chevy shortbed stepside, 4.3 with a 5 speed manual tranny, 248,000 miles. About 3 months ago, the plastic and metal clutch line that runs between the master cylinder and the slave cylinder ruptured. I replaced it, the master cylinder and the slave cylinder. Bled the system, everything worked fine. Two weeks later, the clutch master cylinder ruptured. It's a molded plastic part, and it split on the underside where the parting line is. I replaced it, and the replacement lasted another two and a half weeks, and then it ruptured in the same place. I've done this 6 times now, using 3 different brands of master cylinders (although they all look identical, down to the "Made in USA" molded into the part and the "Assembled in Mexico" sticker). The latest one was from a Chevy dealer, and was an OEM part. Any ideas what is causing this problem? It's a pretty simple bolt on the firewall, hook up the hydraulic line and connect the pedal pushrod installation. No adjustments to be found. The transmission was replaced at 122,000 miles. Could a heavy duty tranny have been put in, and it's causing too much pressure for the master cylinder to handle? Is there a steel master cylinder available somewhere, instead of the molded plastic ones? Any insight to the cause of this problem would be greatly appreciated.
Jul 15, 2010 at 8:45 AM
