Is it normal for there to be a clicking noise while driving along with the center diff locked? I was on a gravel and dirt road testing my new CDL install and noticed the clicking. The noise is not present when the center diff is unlocked. High or low range doesn't seem to make a difference.

 

Not normal.

 

Do you think it's not fully engaging? The light comes on. Will the light come on if it's not fully engaged? I wonder if I need to adjust the cable. I thought I had it so that it was good, but maybe not.

 

It is engaged if the light come on.
Have you ever rebuilt/replaced your front drive shaft, how often do you lube it and when did you last service your t/case and with what weight oil?

 

Very true, it could be putting more strain on your front drive shaft than the vehicle is used to without the diff locked.

 

The driveshaft was replaced about 60,000 miles ago with a heavy duty Spicer 1310 series shaft. The u-joints were replaced 2,383 miles ago with Moog/Precision 380's, including the 612 centering ball. The last time the shaft was greased was 14 miles ago with my last oil change with Mystik JT-6 High-Temp red grease. I think I'll re-grease it a bit as I might have gotten some penetrating oil on the u-joints.

My rear drive shaft I have not serviced other than putting grease in the zerk fittings that are there. I have a new u-joint ready to put in, I just haven't gotten around to that yet. The rubber flex coupling looks to be in good shape. No cracks or visible wear.

The Transfer case was supposedly serviced around 100,000 miles (it is currently at 103,314) by the Land Rover dealer. This was done by the previous owner, so I don't have real specific information, but I do have an invoice with the service on it. I'd assume that they'd use the Texaco Multi-Gear 75W90R oil that is in the RAVE manual. I know I've been reading on here about the different options for transfer case oil. Synthetic vs Dino and 80W90 vs 85W140. My transfer case has been historically very quiet. no whines at all. I do have a slight drip from the inspection cover. It's about 1 drop every three days. Do you think I should do a drain and refill with some other type of gear oil?

 

Can't hurt. Except the wallet gauge. Would also be good time for a magnet to test the drained oil.

 

Ok, I think I will do a drain and refill then. Can't hurt the old piece of mind factor either. I should be able to seal up the leak in the inspection cover then.

 

You might consider adding some White Shepherd oil stop leak along with some 75 or 85/140 gear oil.
Make sure to look closely at the drain plug magnet for any unusual metal chunks or bearin surface.

 

Ok, will do.