Bearing of an idler gear of an all-wheel transfer transmission

A bearing of an idler gear of an all-wheel transfer transmission, said idler gear being disposed between first and second casing walls of a transmission case and mating with both a driven gear wheel originating from an all-wheel locking system and an output gear wheel driving one vehicle axle, comprising:

• a bush on which said idler gear is disposed, said bush having at least one side with a stop collar which rests against said first casing wall and another side which is axially braced on the outside with respect to said second casing wall;
• and
• tightenable connection means for axially bracing said bush with respect to said second casing wall,
• wherein said tightenable connection means is a screwed connection means comprising a screw that passes centrally through said bush and a nut, said screw having a head which forces said stop collar against said first casing wall, said nut resting against said second casing wall, and
• wherein said first and second casing walls include a bore through which said bush is fitted, and further comprising O-rings for sealing off said bore with respect to said first and second casing walls, wherein said O-ring which seals off said second casing wall is between said nut and an end face of said bush.