We've got a 1995 F350 with a 7.3 and zf5 transmission. It has a LuK single mass flywheel conversion. Last summer the master cylinder was replaced. Over teh course of the last 2 months it has blown apart 4 slave cylinders. The shop has called the manf. of the replacement cylinders and they know of nothing that could cause this. The dealer has no clue either. Its sitting in the wrecker yard right now waiting to go to the shop to get this one pulled. I am not ready to trust yet another piece of plastic junk on this truck. Has anyone ever tried to run a aftermarket slave from Howe or Wilwood? I know I will need to replace the master cyl also, because of the type ends on the hose not being normal threaded hose ends. I can't have this truck breaking down every time I turn around to go out of town for business so I'm willing to spend extra $$$$ rather than it be a shop queen. Any help is appreciated...Thanks in advance

 

Dont have any thing for your application exactly but I know Howe and Wilwood make a good product. But f you have gone through 4 slaves that fast I would think you might have a different problem that is causing the slaves to blow out.

 

What gets me is it keeps blowing the seam apart where the 2 halves of plastic meet. What could be out of alignment that much to cause it to split in half? If it was trying to overextend wouldn't it try to rip the pushrod out? Or atleast take a chunk out? Its a perfect split that you can't even see unless you pry the 2 halves apart. I can't see this problem making any sense because this isn't a high pressure system is it? I know brakes can reach 1600+ psi. But I would think the clutch line would burst before the slave? I did a search on google for 3 hours today and all I came up with was one person that said Ford has a TSB out to upgrade the 93-95 master/slave/line to the 96-97 setup. I've got one coming tomorrow morning to see if there is anything different between the 2. I have been told its metal vs plastic so I'll get pics in teh morning. Thanks for the reply

 

Please keep us up to date on what you find! I'm curious now...

 

Well, I didn't get a chance to take pics of the new one that came in. The upgraded cylinder/slave was still plastic but of a different design. The slave cylinder was almost 2x the diameter of the original one and I think it have a bleeder valve which the 95 doesn't have. The master cylinder has a metal push rod like the older ones had I've been told. Mine OE is plastic which broke last year, starting the snowball of clutch related issues I have the up grade one coming from Ford now, along with a few others from other sources just to do a little comparison. The truck finally made it to the shop, so I'm waiting on the call from them to let me know if they find anything else.

 

Any updates??

 

Find something out??

 

Yes, I did. It blew another one apart right down the seam. Said to hell with 95 parts and got the 97 parts installed. Bled out nicely and was better than new...almost. With the 95 style slave it wasn't allowing full travel so the clutch was always engaged. 3 days after teh new clutch master/slave/line assembly I found out the clutch was trashed. I babied it for a couple days to see how it acted, and then on day 3 I let her have it. Shifted nice and crisp...didn't grind going into gear...altho anything over 1/4 throttle I'd redline and truck didn't go. So I got a new clutch, we got that in and I've been testing it. Plenty of long trips. I wish the truck was this good back when I got it last summer. Shifts nice and smooth, barks gears, spins from 2nd in the rain ect. Actually acts like it should with over 300hp( I hate banks...now for the real performance parts)
Drifting a 1 ton is hella fun

 

Will close the thread. If the same problem should come back, can reopen the thread, or start a new one.