TM 10-3930-659-34 5-4. ENGINE MAIN BEARINGS, THRUST BEARING, AND CRANKSHAFT REPLACEMENT (Con’t). 21. Using  inside  caliper  micrometer,  measure  width of thrust bearing journal (15). 22. Using outside caliper micrometer, measure width of thrust bearing (16). 23. Subtract measurement in step 22 from measurement    taken    in    step    21.        Difference between   the   two   measurements   is   clearance. Maximum   allowable   clearance   is   0.in.      (0.381 mm). 5-41