I just purchased a '84 F250 2WD, 460 4-speed manual transmission. This has the hydraulic clutch and the previous owner put a new (NAPA) slave cylinder on it. The truck just shifts stiff. You have to really push to get into the gears. All gears are the same. No grinding you've just got to force more than what I think is normal to get through the gears. Almost like the clutch isn't disengaging enough.
I'm going to try and bleed the slave cylinder and see if that help but wanted to run it through here for any other ideas. Since there's no real linkage to play with on the hydraulic clutch are there any upgrades available to add more to the pedal for disengaging? I thinks its more in the pedal and slave cylinder than the transmission.

Thanks in advance for any info

 

You should have the t-19 which is fully synchronized. Have you tried shifting it without the clutch(after you get moving)? Maybe your synchros could be bad not allowing it to 'fall into gear' until you hit the correct rpm? I wouldn't know for sure or anything but its an idea.
Also try new fluid and bleed it if you haven't already.

 

Let it sit in the driveway idling with the clutch out and the tranny in neutral. Push in on the clutch, count to 5, and then try to put it in reverse. If the gears grind count to 5 again still holding the clutch to the floor, and try reverse again. If you still get gear scraping, your clutch is not working correctly.

It could be something wrong with the hydraulic release system, something wrong with the clutch diaphragm, or you could have the dreaded cracked firewall. Get someone to push the clutch pedal in while you watch the firewall around the brake booster. If it moves alot you might have a cracked firewall.

 

I tried this and no gear grinding or cracked fire wall. Leaning towards the synchronizer issue.

 

Is it the original master cylinder?
Aftermarket masters should have an adjustable pushrod.

Three things to look for are;

1) Worn plastic cross shaft bushings up in the top of the pedal support.
These can get ovaled, and in extreme cases wear into the support itself.

2)The pin on the belcrank arm can get a groove worn in it from the master cylinder pushrod 'eye'.
The arm can also twist on its splines.
You can get a new arm from Ford. (don't have the P/N handy)

3)The four fingered plastic retainer bushing can crack or wear.
If you have a groove worn in the back side of the pin it will fail almost immediately.
These can be found as part of a variety pack of windshield wiper linkage clips in the 'HELP!' section of many parts stores.
http://www.dormanproducts.com/p-32472-49445.aspx

4) If you find no problem with any/all of the above, and an aftermarket master, then loosen the locknut on the piston rod and adjust it out to where you can just slip it on the pin with the pedal in the fully up position.
Clip it on and tighten the nut.

At this point it should be as good as it gets.
There's no reason for the clutch to engage right off the floor.

Remember the T-19 is a TRUCK gearbox. If you're expecting it to shift like anything else you are bound to be disappointed.

 

It's not grinding when he puts it in reverse, so I think the clutch is working. I wonder if it has the wrong lube in it.

 

80-90 GL5 Was always fine in my T-19.

What explains it engaging just off the floor?

 

Just engaging off the floor is probably a worn out clutch. And while he is driving, if he doesn't make a special effort to push the clutch all the way to the floor in that situation, then it might be causing a problem.

 

I've got to dig more into the clutch and the hydraulics associated with the clutch. Looked the pedal over pretty for worn pivot and dont see any signs without tearing the pedal out.

The more I drive it seems as though the clutch may be dragging a little. Even in the driveway it has to hit just right on the rpms to drop into gear easily. Kind of like push the clutch in, wait a second and then it slides in. Strange trying to explain. Absolutely no gears grinding just stiff getting it to drop into gear.

The previous owner installed a tack so he could shift without using the clutch. I wonder if he messed something up trying the shifting without the depressing the clutch pedal?

I dont think it normal for stiff shifting. Although this is my first everyday driver ford truck, I own/drive an original 1928 Model A and have a 52 F4 and a 52 F6 I put a 337 Flathead Lincoln motor in it with a 5 speed F7 transmission w/2 speed rearend and they all shift easily.