use brake fluid
If it is a stick, it could most likely be the clutch master cylinder or the slave cyliner. Check around the master for any leaks. Also, check the transmission itself and the clutch pedal in the cab. If there is fluid on them, that is probably your problem. Another thing could be the clutch pressure plate. If it is an automatic, check the transmission fluid and consider a transmission service.
your transmission is most likely bad if it an automatic but if it a manual then your clutch could be bad
if it is a manual talon could be clutch not disengaging( slave or master cylinder most likely culprit) if automatic, could be something to do with tranny itself or shifter
Manual transmission: Clutch Automatic transmission: possibly low transmission fluid
If we are talking about a clutch slave cylinder for a standard transmission, yes it could.
You have to shift gears in all of them, so you'd call them "manual," but in 1969 you could get an "autostick" transmission that had an automatic clutch connected to a manual transmission.
NO, Break Fluid Only
clutch plates could be welded to gather
If you're POSITIVE the clutch slave cylinder isn't leaking, there's only two other places it could come from. The clutch master cylinder or the hydraulic line in between the master and the slave cylinder. Maybe I'm confused. Isn't the clutch Master cylinder the one that the owner would check, and the slave cylinder inside the transmission?
It is impossible to 'convert' an automatic transmission into a manual transmission. You car replace the automatic with a manual, which also requires installing a clutch pedal, clutch cable, or clutch master and slave cylinders, as well as a shifter and shift linkages. Check at local junkyards for a car about the same year, make, and model as the one that you have which has a manual transmission, remove, or have removed, this transmission, including the clutch and bell housing, and install these in your car.
Go to the transmission and check slave cylinder for leaks,also check clutch master cylinder,then go look by your clutch pedal to see if its leaking there,these are your places that it could be leaking,is your fluid level low,if not ,then you may need a new clutch kit.
Assuming your car has an automatic transmission, it could be the TCC (Torque Converter Clutch) solenoid.