Clutch slippage issues

[Miller]

So, I replaced my clutch with a LUK kit last year. Since then it's never really grabbed like I think it should. Most of the time it does just fine, but if I'm messing around and really on it, the 1-2 shift will slip the clutch something fierce. It always ends up grabbing, but the slipping is SO annoying when I'm trying to compensate for something around friends. Or trying to go as fast as possible because of illegal activities, either way.

My point is this, I've been thinking, my stock clutch went out (58k miles, which isn't unheard of unfortunately) only a couple months after I replaced my master cylinder. So this got me thinking! What if the master cylinder had something wrong and caused the first failure and is causing this to not grab. I REALLY don't want to drop the trans again, what a PITA, so I'm trying to brainstorm what could be causing this! Also, I saw some dark fluid around the seam between the block and trans. Looked like a bit of engine oil, but it was impossible to tell where it came from because the whole under body was filthy.

I guess I'm looking for insight and wisdom, so let me hear your thoughts!

[tgnorman]

The only way I can think of for the master cylinder causing reduced clutch life is if it's leaking/defective and not fully disengaging, causing the disc to drag and wear prematurely.

In all honesty, I'm convinced the stock replacements are junk, mine felt great for about 5k and got mushy and sloppy after that.

[spots25]

well if your rear main went and soaked the clutch, yeah, it'll be shitty

how did it look when you replaced the clutch? Did you resurface? New pressure plate?

[Miller]

whole new kit. plate, flywheel, clutch, slave

[Steve@Tasca]

The only way I can think of for the master cylinder causing reduced clutch life is if it's leaking/defective and not fully disengaging, causing the disc to drag and wear prematurely.

In all honesty, I'm convinced the stock replacements are junk, mine felt great for about 5k and got mushy and sloppy after that.

Hey Karl, did you use the actual OEM slave or one frm an aftermarket kit?

I have heard of a lot of issues with aftermarket ones but not so much with the one Ford sells.

Miller, is your brake fluid level dropping? Could be a sign of a leaky slave cylinder.

[Miller]

No brake fluid loss. So I'm hoping it's not the rear main. I'm going to bleed it very well and see if maybe there might just be a bubble causing chaos or something before I go and start dropping the trans... again. Especially since recent orders prohibit me from ordering a LSD while I'm in there.

And lets not forget I still need to fix my power steering leak.

[Steve@Tasca]

No brake fluid loss. So I'm hoping it's not the rear main. I'm going to bleed it very well and see if maybe there might just be a bubble causing chaos or something before I go and start dropping the trans... again. Especially since recent orders prohibit me from ordering a LSD while I'm in there.

And lets not forget I still need to fix my power steering leak.

Air bubbles wouldn't cause slippage, that would cause the clutch to not fully disengage and could cause hard shifting but not slippage.

[Miller]

Unless they are just slowing the rate the fluid is moving through the system? Then I could see it causing a lag in both engaging and disengaging of the clutch.

[Steve@Tasca]

Unless they are just slowing the rate the fluid is moving through the system? Then I could see it causing a lag in both engaging and disengaging of the clutch.

Nope, the disengagment is all from the springs in the pressure plate. Air bubbles have no effect on that.

[Miller]

Makes sense, I was just thinking the compressibility of the liquids (air can be viewed as a liquid in circumstances of flow) that bubbles could cause issues with how everything acts. It's a stretch, but who knows.


To be more accurate, it's not really slippage. It just fails to engage fully (as in takes a while for the trans engine and trans speeds to match, just takes a bit to engage) on full throttle shifts mostly between 1-2. If I let off the gas and let the idle come down a bit and allow the clutch to engage before gassing again, it doesn't slip at all.

[tgnorman]

The only way I can think of for the master cylinder causing reduced clutch life is if it's leaking/defective and not fully disengaging, causing the disc to drag and wear prematurely.

In all honesty, I'm convinced the stock replacements are junk, mine felt great for about 5k and got mushy and sloppy after that.

Hey Karl, did you use the actual OEM slave or one frm an aftermarket kit?

I have heard of a lot of issues with aftermarket ones but not so much with the one Ford sells.

Miller, is your brake fluid level dropping? Could be a sign of a leaky slave cylinder.

Eh, it's the LUK replacement that came with the kit. Not sure on that count...

[Steve@Tasca]

Eh, it's the LUK replacement that came with the kit. Not sure on that count...

That could be a problem, I have seen a number of failures of the ones that come in aftermarket kits.

[Miller]

I replaced my slave with the LUK is that what you guys are talking about, or are you talking master?

[tgnorman]

Eh, it's the LUK replacement that came with the kit. Not sure on that count...

That could be a problem, I have seen a number of failures of the ones that come in aftermarket kits.

I thought the LUK slave was the same part that Ford sold....

[Miller]

I think I may have a solution to my problem.

I ran low on coolant last week and when I felt under my thermostat housing I felt liquid and sure enough it was green/clear.

So I could see the fluid running down into the transmission case.

The problem I have with this theory is, why did my clutch start acting that way immediately. I mean, I guess is could have been at the Auto-X at CC. It was pretty hot out that day....

Either way, I will be replacing my t-stat housing at the very least.

Could this be that problem? Anyone else had something similar?