I've been working on getting my Disco ('97 with AT) ready for some off-road use, and have occasionally put it in low range to keep the shifter working smoothly. I'll drive around for a few minutes also, just to ensure everything functions correctly. What I have noticed, since I bought the vehicle, is that the shifts are very abrupt ONLY when in low. Is this normal? There is no noise, but it feels like there is a big pause, then a big momentum push forward as the next gear is selected.
Does this seem like a potential transmission issue? Or a TCase problem? The shifting appears to be fine when in high and does not matter whether diff is locked or not.
Any insight would be appreciated. I am going to be changing the T-Case Gear Oil along with other fluids.

 

Most likely normal and you are not used to it.
Have you done my major service list posted in the top of this section, it is a good guide towards getting your tuck current .

 

Sounds normal. There's a lot of torque in low range that can make the truck feel jumpy.
Don't drive around on pavement with the diff locked.
Buy 7qts of gear oil and do the TC and both diffs at the same time.