I have a Landrover TD90 which is 12 years old (registered in 2000). I use it in the mountains and take it up some fairly serious inclines when felling timber.

Today I noticed that the traction is much better when in a forward gear than in reverse. I have permanent 4 wheel drive, was in low ratio with the diff lock on. A friend of mine, standing behind the landrover, wasn't sure that the diff lock was working in reverse gear.

Should it work when in reverse?

 

If its locked I shouldn't matter which direction you're moving

 

What made your friend think it was not working in reverse?

 

Are you running tires with directional tread? That can make a difference.
Also, terrain can make a difference (up hill/down hill) because of weight distribution.