How to Adjust an Eaton Fuller Clutch
Eaton Fuller heavy-duty clutches are adjusted at the clutch, not at the pedal. The measurement that matters is the gap between the release bearing and the clutch brake, and whether you can adjust it at all depends on which clutch is in the truck. This guide follows Eaton's service manual CLSM0200 for Easy Pedal, Easy Pedal Advantage, EverTough, ValueClutch and Advantage Self-Adjust clutches.
Which Eaton clutch do you have?
| Clutch | Adjustment |
|---|---|
| Easy Pedal, Easy Pedal Advantage, EverTough Manual Adjust, Reman Manual Adjust | Manual internal adjustment with the Kwik-Adjust nut |
| ValueClutch | Manual internal adjustment with a lock strap and adjusting lug |
| Advantage Self-Adjust, EverTough Self-Adjust, Reman Self-Adjust, Heavy-Duty ECA | No adjustment. Two opposing cams take up wear as the clutch is used. If the gap is inside 0.490 to 0.560 in, leave it alone. |
| UltraShift DM | No adjustment and no clutch linkage |
Eaton does not recommend a manual-adjust clutch on a truck with hydraulic clutch linkage; a self-adjust clutch is the recommended fit there. If you are not sure which clutch is installed, the cover stamping and the presence of the Kwik-Adjust nut through the inspection opening will tell you, or send us a photo.
The specifications
| Measurement | Specification |
|---|---|
| Release bearing to clutch brake, manual adjust clutches | 0.500 to 0.560 in (12.7 to 14.2 mm) |
| Release bearing to clutch brake, self-adjust clutches | 0.490 to 0.560 in |
| Release yoke fingers to bearing wear pads (free travel) | 1/8 in (0.125 in, plus or minus 0.020 in), measured on both sides and averaged |
| Clutch brake squeeze | A 0.010 in feeler gauge between bearing and brake is clamped with the pedal on the floor, and frees about 1 in from the end of the pedal stroke |
| Minimum total yoke finger travel | 0.685 in (0.125 free travel + 0.500 bearing travel + 0.060 brake squeeze) |
Take the bearing-to-brake measurement with the pedal depressed just enough to remove the free play in the cab, using a telescoping gauge or transfer dividers through the inspection opening. Do not force a bar into the gap.
When to adjust
- Free pedal in the cab has dropped to half of the truck maker's specification. Never let it fall below 1/2 in. As the facings wear, the release bearing moves toward the yoke fingers and the free pedal shrinks.
- The clutch brake no longer stops the input shaft for a clean shift into first or reverse at a standstill.
- The clutch slips. Check the internal adjustment and the linkage first. If both are correct and it still slips, the clutch is worn out and needs replacing, not adjusting. A slipping clutch builds enough heat to destroy itself quickly.
- On a self-adjust clutch, too much or too little pedal travel before engagement, or the wrong clutch brake squeeze, means measure the bearing-to-brake gap and read the wear indicator through the inspection window. A tab at or near REPLACE means a new clutch.
Internal adjustment, Easy Pedal and Easy Pedal Advantage
- Remove the inspection hand-hole cover on the clutch housing and depress the pedal to take up the cab free play. Measure the release bearing to clutch brake gap. If it reads 0.500 to 0.560 in, skip to the clutch brake squeeze check.
- Have an assistant hold the pedal down. The clutch must be released for the adjusting ring to turn.
- Facing the engine, push the Kwik-Adjust nut in and turn it: clockwise if the gap is more than 0.560 in, counterclockwise if it is less than 0.500 in. The nut is a six-position spring-loaded adjuster and takes a common box-end wrench, with no bolts to remove.
- Release the pedal, depress it again and re-measure. Repeat until the gap is inside 0.500 to 0.560 in.
- Check the 1/8 in gap between the yoke fingers and the bearing wear pads. If it is off, correct it at the linkage or the upper pedal stop. Do not correct free play by moving the bearing.
- Check clutch brake squeeze with the 0.010 in feeler gauge as described above.
- Grease the release bearing and refit the hand-hole cover. Dirt through an open inspection hole seizes adjusting rings and self-adjust cams.
ValueClutch: with the pedal held down, remove the lock strap and move the adjusting lug to the left if the gap is over 0.560 in, or to the right if it is under 0.500 in, then refit the lock strap.
Resetting a self-adjust clutch
A self-adjust clutch only needs resetting if the gap has closed below 0.490 in, which usually means the transmission was pulled with the release arm still engaged. With the pedal on the floor, rotate the engine until the cam tab is visible through the inspection opening and push the tab to NEW with finger pressure (a blunt tool if needed). Install the four shipping bolts hand-tight only (7/16-14 x 1-3/4 in on 15.5 in clutches, 3/8-16 x 1-1/4 in on stamped 14 in clutches), remove them, stroke the pedal five times and re-measure. The gap should sit near 0.750 in and settle into specification as the cams take up.
Parts you may need
- 125489 Kwik-Adjust spring-loaded adjuster nut
- Clutch brakes: 127740 torque-limiting, 1.75 in spline, 127760 torque-limiting, 2 in spline, 127200 two-piece, 2 in spline
- Inspection hand-hole covers: 4305231 (no lube hose) and 4305230 (with lube hose)
- Installation kits with the release bearing, bushings and clutch brake: K-4145CL, K-4264CL, and the AT-200-14 alignment tool
- Complete clutches: Eaton Fuller clutches by size, spline and torque rating
Not sure which clutch or clutch brake the truck takes? Call 877-776-4600 with the transmission model and engine, or use the Eaton transmission identification guide. Other guides are in Identification Guides.