The stock linkage is basically pins that engage in holes and wears badly and drags.

The new and improved version uses 3/8" ball joints and a new Z arm, modified to have better leverage.

In the picture, the stock push rod ( that broke) is replaced by a ball joint that threads into two, 3/8" threaded rod coupling nuts welded together. Very strong, almost no excess play and adjustable.

The Z arm assembly was replaced with a GM part but the arm near the clutch was at the incorrect angle to apply force to the clutch lever at a 90 degree angle. A piece of steel was welded to the arm on the clutch lever side and 3/8" hole drilled in it to move the pivot point one inch closer to the clutch arm. The clutch arm travel was 0.8 inches to disengage the diaphragm type clutch.

The coupling nut at the clutch arm has the shoulders ground down to not rub against the clutch arm. There is a large bearing ball between the two and the coupling nuts are filled with grease to lube the ball.

There are two springs, one to hold the linkage in contact, the other long one to pull the throwout bearing away from the clutch fingers. A 4 inch arm was added to the clutch arm as a place to attach the long spring so it doesnt rub on the linkage.

There is also a ball joint on the Z arm to receive the clutch pedal push rod coming down from the clutch pedal.

It works very well. Smooth and greaseable and almost no lost motion.

The clutch push rod at the pedal had worn the pedal lever badly. The lever was drilled 5/8" and a 3/8" steel one piece shaft collar was welded on the outside ( left side facing front from the drivers seat) to receive the 3/8" pin on the clutch rod.

The pedal lever pivot was fitted with a bronze oiled bearing, 0.382 x 0.690 x 1.5" (7/16 x 11/16 bearing) and the thru bolt was smoothed with a file. That eliminated slop in the pedal travel.

78 K5 modified clutch linkage. Clutch arm at top right


The ball joints have grease fittings. Due to the heat, Id not use sealed units without grease fittings, the grease will dry out. In the picture below, the shaft collar does not have a grease fitting but does have a threaded hole for a setscrew; put a piece of stiff felt in the hole and oil the felt occasionally.

 

Clutch pedal lever assembly showing bronze bearing where bolt passes thru, and shaft collar welded to the lever above to right.

 

Ball joint linkage. Grease zerk on top side of ball joint head. Large bearing ball with grease at the left end of thenuts welded together. The ball joint is mounted to a small piece if steel welded to the stock Z arm.

Ball joint threaded into coupler nut welded to a spacer to the Z arm. The rod above comrs thru the floor from the clutch pedal.