IRD or Gearbox Failure - Diagnosis

Hi ,

TD4 Manual 2003.

Symptoms

Will only drive forwards 3-4 meters then seems to seize up then crunch. Definitely something in the front half of the drive-train.

IRD or Gearbox ? Happens in forward and reverse gear !

sounds like ird, but could also be rear diff. have you tried dropping rear prop ?

Havent tried anything yet - its currently stuck in a car park awaiting recovery !

With gearbox in neutral…

Lift both front wheels off the ground. Turn one and the other will turn in the opposite direction. Tests front diff in ird.

Lift both rear wheels off the ground. Turn one and the other will turn in the opposite direction. Tests rear diff.

Lift 2 wheels on one side. Turn one and the other will turn in the same direction. Tests connection between front and rear wheels via ird, vcu and rear diff.

And while your doing the above, do the one wheel up test as per me video below. Failure of the vcu causes extra stress in the transmission. This often leads to ird and or rear diff failure. Hence the crunch you describe.

Thanks Hippo,

Will try all of those and post back