ALLISON 1000 & 2000 PRODUCT FAMILIES
C3 AND C4 CLUTCH PACK COMPONENTS
B. C3/C4 Return Spring Assemblies
C. C3 Backplate
D. C4 Backplate
E. C3/C4 Clutch Pistons
A. C3/C4 Clutch Packs A. Inspect all friction plate contact faces for excessive wear, embedded metal particles, cracking and distortion. Inspect the plate splines for burrs, cracks and damaged spline teeth. Replace the plate if spline damage cannot be repaired using a soft stone or crocus cloth. Minimum allowable friction plate thickness is 2.375 mm (0.0935 inch). Minimum allowable oil groove depth is 0.20 mm (0.008 inch). Maximum allowable coning is 0.225 mm (0.009 inch). NOTE: Anti-freeze (glycol) and/or
water will adversely affect the bonding agent between the friction material and steel core. Replace any 48
ALLISON
TRANSMISSION
2005 General Motors Corporation.
friction plates which have been exposed to water and/or glycol. Friction material which is loose or flaking indicates that the plates have been exposed to glycol and/or water. Reference SIL 18-TR-98, Rev. A for details.
crocus cloth. Replace the plate if any tangs are broken, bent or otherwise distorted. Minimum allowable plate thickness is 2.440 mm (0.0961 inch). Maximum allowable coning is 0.40 mm (0.016 inch).
NOTE: Battered and worn spline
B. Inspect the C3 and C4 clutch
teeth may be an indicator of driveline issues. Replace the clutch plates and check the driveline. Inspect reaction plate contact surfaces for chips, cracks, grooves, scoring and signs of discoloration. Inspect reaction plate tangs for chips, cracks and signs of battering. Replace the plate if damage cannot be repaired using a soft stone or TECHNICIANS’
GUIDE
return spring plates for cracks, chips, burrs, bends and distortion. Replace the plate if damage cannot be repaired using a soft stone or crocus cloth. Replace the spring assembly if springs are broken, cracked, permanently set, showing signs of wear due to rubbing or showing signs of discoloration. (continued)
