Clutch is almost gone

[WarrenG]

Hey there,
I've got a '74 100 with a 4 speed in it. The clutch is just about gone(pedal is almost all the way out before it grabs but it grabs strong).
I'm moving in a couple weeks and I'm not sure if that clutch will make it. It has to go 200 miles and over 2 mountain passes. Moving from Wenatchee, WA to Olympia, WA
Does driving at highway speed wear out a clutch more than when your city driving and shifting gears all the time? Does speed have anything to do with wear of a clutch?
Go ahead and educate me.
Thanks in advance

[Paul "Misterfixit" Schulz]

low revs and a light throttle pedal application are the way to make a slipping clutch last untill you get home, if its grabbing at the top of the pedal travel, make sure you have a little free play at the thrust bearing - you may put off that clutch job for 6 months.

[WarrenG]

So if your not shifting gears and just running a steady 60 mph, is there any wear on the clutch?
Warren

[Baradium]

AFAIK most of the wear is from the stopping and going. Adjust the linkage to see if you can get any more pedal travel out of it (the more travel the better it can grab and longer it'll last). As long as it isn't slipping right now it'll last a while longer.

[Bill Bennett]

It may just need some adjustment. Be sure there is 'freeplay' in the pedal.
If the throwout bearing is always rubbing against the clutch forks, you will lose the throwout bearing. When you check for clearance for the clutch, get under the truck and get some grease into the throwout bearing. And 'U' joints and slip yokes.
Bill Bennett

[Scott L]

Or you will lose the clutch forks (ask me how I know). Heat and pressure lead to fatigue cracks, bending, and for one of them, a clean split.

[Mark Greven]

If you are running at a steady speed or even a range of speed such as the top grear range from 35 to 70 and don't shift you won't have any wear, because you aren't shifting. The clutch won' be slipping as long as you don't try doing burnouts with it right now. and like the others said, I'd adjust the linkage as well for more pedal. Even an inch is good. You don't want too much or you will put the throw-out bearing forks into the pressure plate fingers. Not good. Try a minor adjustment for about an inch.