tightening diff pinion nut

[Bruce]

One of the items for my road worthy was to tighten the diff pinion nut.

Everywhere I have read about this is pretty non specific about how to tell when it is tight. Has anyone got any tips on how to do this correctly?

cheers

Bruce

[Enzo]

Hi Bruce,

The pinion nut to the diff should be tightened up to 120lb/ft (16.6 kg/m ) initially. At this point you can check the bearing preload by the spring balance method. This is described in the Haynes manual if can borrow one. Basically fit a spring balance to one of the bolt holes on the drive flange and pull. The tailshaft should be disconnected at this stage. The force required to move the flange should be between 7 and 9 lbs (3.2 to 4.2 kg ) Lock the hand brake on and go for it. If the hand brake will not hold, use a large screwdriver or tyre lever to stop the drive flange from rotating. If the tension is not between 7 and 9 lb tighten the pinion nut up in 5lb/ft (0.7kg/m ) increments till it is. Hope this helps. Regards David

[Enzo]

HI Bruce,

Should have said the simple way was to disconnect the tailshaft, lock on the hand brake and tighten the pinion nut. If you want to check the preload tension disconnect the half shafts then fit the spring balance to the flange. If the preload is not right refit two of the bolts in the flange and fit a screwdriver or tyre lever between the bolts to stop the diff turning. Now with a tension wrench retighten the pinion nut and recheck for preload again. Keep checking till preload correct. David