I think the 1987 has the LT230 transfer case because I brought a spare Auto and Transfer out of one and that's what it had.
If this is the case pushing the level forward and back selects High and low range with the centre diff open. Pushing the level to the left locks the centre diff. This can be done in high or low range. Also the lever should move from high to low in the left position. Sound like your linkages might be a bit jammed up.
In your case you should have had the lever forward and to the left for Low/Centre Diff locked. This will give you drive to both front and rear wheels at the same time. I think it would be near impossible to stop the wheels moving in low range unless there are some issues with the driveline somewhere.
Try going into low range on the road. You will soon know if you are.
Cheers, David.
My Land Rover has made me a better Mechanic........
D2 TD5 Manual, CDL, Detroit Rear, Truetac Front, 2" OME lift, 32" MT Tyres, ARB Bull Bar, Winch, TJM Roof Rack, Driving Lights, Dual Batteries, ARB Side Steps, Rear Draws, Uhf.
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