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Selecting Shims

  1. Shims can be selected using 2 methods. One method is using a shim selection chart. If this method is preferred, go to next step. Other method is using a formula. If this method is preferred, go to step 3).
  2. Using micrometer, measure thickness of used shim (shim that was removed). Using measured clearance and used shim (shim that was removed) thickness, determine correct thickness of adjusting shim to be used. See Fig 1-19.
  3. On ES300, GS300 & SC300, shims are available in thicknesses of.0984-.1299" (2.50-3.30 mm), in increments of.002" (.05 mm). On GS400, LS400 & SC400, shims are available in thicknesses of.0787-.1102" (2.00-2.80 mm), in increments of.0008" (.02 mm). On models, using a micrometer, measure thickness of used shim (shim that was removed). Use the following formulas to determine how thick the new shim should be:
    • Intake Valve:  Subtract.008" (.20 mm) from the measured (actual) valve clearance. Add the result to the thickness of the used shim. The final result represents the thickness of the new shim.
    • Exhaust Valve:  Subtract.012" (.30 mm) from the measured (actual) valve clearance. Add the result to the thickness of the used shim. The final result represents the thickness of the new shim.
Fig 1: Intake Valve Adjusting Shim Selection Chart (ES300, GS300 & SC300)
G98D10440Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Exhaust Valve Adjusting Shim Selection Chart (ES300, GS300 & SC300)
G98C10761Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Intake Valve Adjusting Shim Selection Chart (GS400, LS400 & SC400)
G98E10763Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 4: Exhaust Valve Adjusting Shim Selection Chart (GS400, LS400 & SC400)
G98F10764Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002