Hi All,

While waiting on time to diagnose / fix my powerstroke, i thought it would be a good time to ask this.

the PO of my truck said ther was an older but rebuilt zf5 put into my truck. I dont know if the clutch is stock or not.

PO told me it had a big boy clutch, but this is but this is the hardest clutch I have EVER stepped on. For reference, I've driven a 95 freightliner with a 425 Detroit in it, as well as an SR20DET with an HKS dual pressure plate clutch in it, as well as late 50s massey 135 tractor, and late 70s massey 175 diesel. Dad, who was an OTR trucker for years, and owns the farm equipment, said the same thing.

Its so hard that when you wanna ease off the clutch, you have to use your hamstring instead of flexing your ankle. it will nearly throw your knee into your chest.

Well, I just read on here that the older F-series trucks had larger master cylinders or something, so that got me to thinking that maybe the cylinders in my truck arent enough to handle the older zf5.

Am I onto something?

I guess what i wanna ask, is if an older zf5 was swapped into a 94.5 truck, do i need to swap the master and slave too?

Should I get an older master/slave combo? Or would a harder aftermarket clutch have an accompanying master/slave that the PO just never bought?

I suppose I could just swap the clutch to a newer model, but dont really wanna go that route.

 

They are all the same from what I know.

I do know that the big box store master/slave combo's are smaller than the stock.

What I'm saying is the slave cylinders from autozone and stuff are smaller and not as strong.

You probably have one of those in there.
I've only seen one OBS with a super stiff clutch and nobody knew why. (i'm going to bet it was this reason anyways, but they wont admit it)

I have a heavy duty pressure plate, i guarantee heavier than the one in your truck, and it's easy peasy to press in.

 

There could be a number of reasons the clutch is acting like crap though.

Throwout bearing not lubricated properly.
Throwout bearing is catching on guide rod.
pressure plate is just ... well, ****.
Clutch fork bent.
Clutch fork pivot bushing wore out.

thats most of the reasons that can be an issue.

 

I had a 91 IDI dually factory 5 speed. It had the stiffest clutch I ever used. Worked well, just very hard to push.... I put the tranny, master and slave from a 93 IDI into my 97 PS with a new Valair clutch kit. It is an easy push. I would think maybe a bad master or slave. Perhaps the line is partially clogged.

 

I have seen numerous aftermarket clutches that were hard to push on the OBS and earlier trucks. It usually happens after someone smokes the clutch, not sure why. I know Ford had a problem with firewalls cracking because of this years ago.
A customer of mine has a 94 F350 IDI turbo that he tows heavy with. We put in 3 different clutches that did this within 6 months. After installing a Centerforce clutch, which uses a Valair pressure plate, he hasn't had an issue in several years.

 

So I guess i need to see if the master/slave are OEM or not, as well as visual inspection of fork, pivot bushing, whatever i can see with the naked eye. I was basically going to just "deal with it" until this clutch goes out. But if it was something cheap, i wouldnt mind going ahead and replacing the faulty part.

Thanks everyone for the replies.

 

Also, if anyone could tell me WHICH centerforce clutch to get for my truck, i would greatly appreciate it. A quick search without research turned up a LOT of different models.

I'm never one to shy away from research, but if someone knows off the top of their head, it would save me some time in the future.

TiA

 

Just a word of advice, stay away from the ceramic button clutch unless you want a very "grabby" clutch. The dual friction is what we put in my customer's truck and it has held up well.

http:// http://www.centerforce.com/products/product-detail/id/CTF-DF067303/name/dual-friction-clutch-cover-disc

 

most of us here run valair.

Made in 'merica!

 

Awesome, thanks

its weird that centerforce doesnt let me select a 94 or 95 f350; they dont even have it listed.

 

http://www.centerforce.com/products/...tch-cover-disc
This link is for a dual friction for a 95 F350 PSD

 

^thank ya. this will be the one i purchase, when the time comes.

im kinda hoping i can find something cheap on mine that can be replaced to soften the feel. If not, i will wait till she starts slipping and replace the whole shebang.