I'd like to put a 4-speed in my truck and, judging from the number of other posts on the topic, I'm not the only one.

Anyway, I'm curious why those who chose to go hydraulic mentioned only aftermarket clutches. My '87 service manual says all 6-cylinder trucks w/manuals have hydraulic clutches. Are they too rare or expensive to use now? Too difficult to adapt to cars?

John

So far as I've observed and torn apart:

Those that got the A-833OD ended up with a 10" clutch and standard bellhousing (starter on top, but later versions had a clutch fork with a ball stud instead of the square piece of metal and the breakable spring clip)

Those with the NP435 and the 11" clutch have the hydraulic slave cylinder style clutch (still uses a clutch fork, you just have a spare "master cylinder" somewhere on the firewall, and a 'pusher' unit bolted to the bellhousing).

-D.Idiot

Thank you, but I'm not sure I understand. Do you mean the hydraulic 'pusher' will only work with the big New Process bell housings?

Doesn't affect me since I have a truck, but I'm curious.

John

He means that an external slave cylinder is bolted onto the outside of the bell and it is what actually moves the clutch fork. So yes to use the external slave cylinder properly you would need a bh that has the mounting boss for the cylinder. I personally have never seen hyd slant clutches from the factory. What year did they start?

<< So yes to use the external slave cylinder properly you would need a bh that has the mounting boss for the cylinder. I personally have never seen hyd slant clutches from the factory. What year did they start? >>

I know next to nothing about working on vehicles. For all I know, 1987 might be the only year hydraulic clutches were used. I'm just going by what my service manual says.

I guess I'm really going to show my ignorance now, but couldn't a mounting bracket be made for the slave cylinder so it would work with any fork on any bell housing?

John

Yes ofcourse it is possible. But there could be problems that could come up like getting enough travel to disengage the clutch. Also you would still need a clutch peddle assymbly with a master cylinder which might be a bit hard to find if it is only one year model that has them and then you would still need to adapt it to a car. I am sure if you put the time into it and had some fab skills it could be made to work and wouldnt even have to be stuff off of the one year model truck you speaking of. You may even be able to find a factory Hydo Throwout bearing that could be made to work. But basically if you can get a master cylinder hooked up to your clutch peddle and get the slave hooked to the bellhousing and can get enough travel to work the clutch and not have to much pressure on the clutch to cause it not to engage properly you would have it working. The diameter of the piston in the Master would have to match & work with the piston size in the slave to achive the right amount of travel.

Jess

Jess: << Yes of course it is possible >>

Hey, thanks. I appreciate the explanation. I knew I was missing something, but I didn't know what.

John

I wrestled with this problem on an off about a year ago. My '64 d100 had a stock hydro clutch with slave, and the problem for me was when I swapped trannys from the stock 3 speed to a 4 speed A833, the shift fork changed from passenger side to driver side. I like the feel of the hydro clutch so wanted it in the 833 bell. I just never did trust the hydro TOB so punted to start again and put in a wilwood slave pull on the frame to pull the clutch fork, and it works GREAT. I used the old MC for a clutch MC connected with steel line to the slave. Feel is stiffer than the old clutch was, but feels great. You can almost tap it and shift. 'Course I have caused myself a problem I am asking about in this forum tonite, but it is about too much grease, not about working or not. I can give you part numbers is you want.
rock
'64d100