hubs / diff issue

[Safaribased]

Hi my name is Mike and I have recently bought a 1992 Nissan Safari Granroad SWB. It's a great vehicle but seems to have an issue with the front locking hub (I have a manual switch on front tryes).

When a bought the vehicle, the bearings on the tyres were switched to "auto", rather than "lock".

But after a while a loud rattling sound started, which was followed by a loud thud. I have since switched the bearing to "lock" and the problem has gone away.

My vehicle also has an electronic "diff lock" switch, which I haven't needed to use yet.

Can someone please tell me whether there's any issue with leaving my truck in the "locked" position. Does this effect fuel efficiency ? What are the "auto" "lock" hub options actually used for and what may be the issue with the rattling sound when the switch is turned to "auto". ?

Thanks for your help.
Mike.

[coxsy]

yes your front diff is now rotating when you drive wearing out the whole front axle assembly and tyres flick them back to auto revercing unlocks auto hubs ,auto hubs engauge when the truck is put in 4wd and the front axle is drive via driveshaft, auto is the std position for these hubs
better yet pull them off and buy some manual hubs for it,
rear diff lock only actives at certain speeds in 4wd don't touch it till your off road and in low range

[Safaribased]

Ok, thanks. So I should leave it in 'auto', rather than the 'lock' position ?

Or is ok to leave it in the 'lock' position ?

Cheers

[coxsy]

auto is the non 4wd place for the hub lock