3308718 - S23 NOISE' GEARBOX / IN A SPECIFIC GEAR

With the engine running, a noise is heard (whilsting inside the gearbox) when a specific gear is engagedThis noise decreases or disappears on changing gear.
Results of the tests
1CHECK ON SYNCHRONIZER RINGSAll OKProblems metOperation
Overhaul the gearbox (see OVERHAULING GEARBOX Assembly 2110B).In particular, check the synchronizer rings for the gear involved: they should not show signs of wear on the inner surfaces Continue to Step 2 Seals wornReplace the synchronizers
2CHECK GEARSAll OKProblems metOperation
Overhaul the gearbox (see OVERHAULING GEARBOX Assembly 2110B).In particular, check the teeth of the gear concerned: they should not be worn or show signs of seizing Continue to Step 3 Gears wornReplace the gears involved
3CHECKING THE CROWNWHEEL AND PINIONAll OKProblems metOperation
Check the crown wheel and pinion reduction gear (see OVERHAULING GEARBOX Assembly 2110D)

In particular:

  • it should not be worn or damaged
  • there should not be excessive clearance
Continue to Step 4 Reduction gear damagedRestore the clearance or, if necessary, replace the crownwheel and pinion
4HECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'