Three Finger to Diaphragm Clutch

[WorkinLonghorn]

Ok, I asked about this in a thread that I hijacked but I still need info.

I have a 12" clutch that has the stock type three finger long clutch I believe and it has pretty much ruined my knee driving in this L.A. traffic. I want to keep this truck if I can get the peddle effort down considerably. It was mentioned in another thread that the diaphragm clutch is easier to work. I need to know how much easier is it. The current clutch seems like about 40 Lbs. to depress and that adds up with 300 reps a day for the last 35 years. Any insight much appreciated. -BA

[oneshotkyle]

Diaphram is your only option for a lighter weight clutch pedal. Lever clutches have there place but not as user friendly in a driver. You could change to hydraulic for a easier clutch pedel effort.

[1970 CST Short Wide]

I went with a hydraulic clutch in my truck. Petal is like Butter

[pjmoreland]

I have a diaphragm clutch and stock mechanical linkage. My impression is that the clutch pedal is reasonably easy to press. I put a bathroom scale on the pedal, and it took around 65 lbs to press it.

[WorkinLonghorn]

Originally Posted by pjmoreland

I have a diaphragm clutch and stock mechanical linkage. My impression is that the clutch pedal is reasonably easy to press. I put a bathroom scale on the pedal, and it took around 65 lbs to press it.

That seems pretty high. I think I'll look into diaphragm with hydraulic linkage.

[WorkinLonghorn]

Originally Posted by 1970 CST Short Wide

I went with a hydraulic clutch in my truck. Petal is like Butter

How difficult is the conversion and is there a write-up somewhere or did you just figure it out yourself. What years had the hydraulic as standard? Thanks

[Steeveedee]

I'd try using a hydraulic clutch with the three-finger style pressure plate before changing out a potentially good clutch. The two styles of clutches used different length throw out bearings, but I don't remember if there were any differences in the linkages. I seem to recall that the medium duty trucks used hydraulic clutches, though I have seen them on light duty trucks in the '60s. I don't know the rhyme or reason for having different styles. There is probably a difference with the bell housing, come to think of it.

[1970 CST Short Wide]

Look up CaptainFab He’s a member here. He sells a kit to convert your truck to Hydraulic

[Accelo]

The Diaphragm clutch goes over center and will take roughly the same apply force but holding it, on the floor, takes considerable less. The can also fail to return after a high RPM shift, depending on the design criteria.

You are asking somewhat of an open ended question as it very much depends on the clutch manufacture and style. I has s stock 1971 Camaro that took very little effort to hold down. It didn't last very many miles though.

I know your question is about clutches, but I would hope you would consider an automatic with overdrive. Solves all the pedal effort issues. I also understand it that's not on the table.

[72SB]

A diaphragm clutch will be easier to depress than a 3 finger Borg & Beck clutch with either mechanical or hydraulic clutch activation.

My 72 is mechanical linkage, diaphragm clutch. Easy on the leg