Those of you who have either replaced this or had it go out on you, wanted to see if any of this sounded familiar. On mine I have noticed in warmer weather it will start to make a squeaking/chattering sound the more it is used and heats up. (Cold weather it is far less pronounced)

Is this a bad sign that it is on the way out in anyone's experience? I know they are not that hard to replace and I had my eye on the HD replacement that South Bend sells. The clutch in my truck I am fairly certain is not stock. Seems way too heavy and that is why it sort of concerns me a bit. I did replace the whole pedal assembly about a year ago and that helped smooth out the pedal throw quite a bit I will add.

 

I have replaced my clutch master/slave cylinder after the pushrod came out of the cylinder behind the firewall. Below is the thread related to that failure.

https://www.ford-trucks.com/forums/1...on-broken.html

Here is the video I created because there was not one out there regarding changing out the clutch hydraulics.


The squeaking/chattering sound you are hearing, is this sound coming from the hydraulics or from the transmission case itself? I was not aware of it when I first bought my ZF6 truck, but there is a term "clutch chatter" that describes some issues I had with my clutch and flywheel. Below is the thread relate to my journey to fix the clutch chatter I was experiencing.

https://www.ford-trucks.com/forums/1...e-as-well.html

Here is the video I created in an effort to have the FTE help me diagnose WTF was going on with my truck.


You can see the drive line shaking and jerking when the hot spots on the flywheel were "grabbing" the clutch friction surface when starting from a stop or very slowly. This issue was compounded very badly when towing heavy, as I do with my truck. Frankly, I was uneducated as to what was happening and misdiagnosed it as axle wrap at first.

Here is a short video of how the clutch chatter was resolved.


The clutch chatter I was experiencing was virtually non-existent when the clutch, transmission was cold. When it warmed up due to common driving, the clutch chatter was incredibly bad. The new South Bend clutch and resurfaced flywheel have the truck shifting, starting and backing extremely smooth. Having the 2WD LOW in reverse helps a lot, especially when I am backing up the 5th wheel trailer.

Squeaking is probably the master or slave cylinder, but chattering would probably not be the hydraulics. As for the HD ZF6 hydraulics sold by South Bend, don't waste your time or money. If you read through my hydraulics failure thread above you will see where we (FTE) discussed the differences and I even contacted SB regarding the HD hydraulics. I am all for fortifying my truck with HD parts, that is why I bought the SB HD clutch, but the hydraulics is a waste of money.

Regarding the heaviness of the pedal, you could try and remove the spring as it is a return assist spring. If you don't like it, put it back in.

Give us some more information about what is going on and we will get to the root of your issue. I have to stay out of all the 4R100 conversations for the most part because I know JACK about the automatics other than what I read here. It is nice to lend a hand to a fellow ZF6 driver once in a while when they need it. Usually they are fluid related, but I guess that is a good thing and yet another reason why I love my ZF6.

 

My rod squeeks so when it does, i blast some lube on it and goes away...
Never been a sign of it going south. Pedal pressure lets me know something/s goin south...aka TO and/or pilot.

 

The sound I am pretty certain is coming from the rod moving in and out of the master cylinder because it is audible down at the pedal. There doesn't to be any clear signs of trouble beyond that but was just wondering if anybody else's makes this weird noise. It could be nothing.

 

I am fairly certain I have that issue too a little bit with the jerking/grabbing clutch and will probably end up going through it at some point. Cant really afford to right now but it is heavier than I like and want to fix that. No way it is the original one.

 

That is good news then. Should be a cheap and easy fix when needed.

The pushrod connected to the pedal which pushes the fluid through the cylinder is held back by a couple of metal prongs, that is all. They are thin and grab about 2/3 of the surface area at the end of the pushrod. So, metal on metal friction with no lubricant means noise from time to time.

As Timmy suggested, spray a bit of silicone lubricant in there and see what it does for you. Maybe have a hydraulic set waiting to be installed in case yours fails.

 

Boy i wouldn't say those tiny tabs hold 2/3. They might be 1mm wide where they actually bite the rod. I would be afraid to spray any lube on it in case the tabs get lubed and let go of the rod. If its a squeak i would think the pedal assembly where it pivots might be the source

 

Meant to mention hitn that area too...

 

For a long time I thought the squeak and a bit of a clunk I was hearing was from the spring attached to the pedal assembly. So, every once in a while I would lube up the push rod a bit (not a lot) and the spring connection points. This would help for a little while, but the sound would always come back. Turns out the sound was of the ears, prongs, tabs or whatever they are called holding the push rod into the cylinder. Once the tabs let loose and the pedal shot up to the bottom of the dash I replaced the clutch hydraulics.

The sound went away completely and I was glad to see it was not the spring after all.

From what I remember, the tabs were narrow on the outside and got wider toward the inside where they held onto the push rod. They caught the end of the push rod so that it would not come out of the cylinder and allow the pedal to rise to the dashboard. I was pretty certain that they held about 2/3 of the push rod end when new, but as they wear down and eventually fail, I am sure there is much less contact surface there. Luckily (by design or accident) when the tabs fail the push rod stays in the cylinder so that the clutch pedal can still be used.

The pedal or clutch motion (hard pedal or soft pedal) did not change much at all since the only thing changed was the hydraulics. The clutch was still the HD South Bend clutch. I do not see the need to remove the spring as some have with a SB clutch. I have no problems pushing in the pedal and holding it there at a stop light or backing the trailer in if I need to.

 

That made noise too until I replaced it about a year ago. It is fairly easy to replace with the PCM removed. It smoothed out the pedal travel and quieted down the higher pitched squeaks that I could not get rid of by spraying WD-40 or similar on the moving parts. They just wear out apparently.

 

Dammit I may just have to replace it. What did you pay for the OEM kit? SB want's around $200 for their heavy duty hydraulics which seems a little rich to me.

 

If you are talking about the hydraulic assembly, it was around $65 or so. I purchased the LUK CRS021 from Rock Auto, but there are several other choices out there, most of which are listed in the thread linked below.

https://www.ford-trucks.com/forums/1...on-broken.html

Some have a metal composite master cylinder housing, but most don't. The OEM was plastic like most of the replacements, so don't be turned off by the plastic housing. The fact of the matter is that none of these aftermarket assemblies will be as robust or reliable as the OEM assembly. At least it takes 20 minutes to replace it, is cheap and lasts 50,000 miles or so before needing to be replaced.

There is no OEM assembly available any longer.

 

Okay that is pretty cheap. I may just order one of those. That is interesting they don't offer an OEM one any longer.

 

Brute Force from RA..56.00..pf9021
All aluminum construction.

 

I ordered the Sachs replacement unit from Rock Auto and think I will just keep it with me. I will be out on the road in this truck a lot coming up here shortly and don't want something stupid like this to leave me with a tow bill. (I think Sachs is the same company as ZF.)