So many techy questions on here I feel foolish asking this, but I'm a proud new owner of a TDI Discovery and notice the extra gearlever has 'diff' written on it but not '4wd'. Does this mean the vehicle is always in 4wd 100% of the time or does the 4wd click in when I lock the diff?

 

You have permanent 4wd. The diff lock will lock up your Center diff, and you don't want it locked on dry pavement. Hope you enjoy your new rover

 

What wasn't mentioned is that yes you are always in a form or 4wheel drive, but shifting the t/case to one of the lock positions while locking the center diff, you now have equal traction locked into both front and rear axles giving you lots more traction. And yes, don't drive on hard surfaces while locked up, it is real hard on the drive train.
Good luck,
Mike

 

Thanks for replies. Very helpful. I suspected it was always 4wd. I'm pleased to say that for a vehicle that's always in 4wd, it's very economical. My last landrover was a series 2 deisel and that used to guzzle the juice when in 4wd but the discovery deisel seems quite good on fuel. Ref what you say about diff I'll ensure it's only ever engaged at slow speeds and on grass!