...Are there special considerations to take with the hubs locked? Speed, distance, etc?
With everything in good operating condition, about the only thing you have to concern yourself with is if you're in 4wd and doing a tight turn. At those acute angles the front u-joints are at their weakest. So if you're doing turns, just keep a light touch on the throttle.
Otherwise, there are no restrictions that I can think of for running with the hubs locked.
In fact, in your situation you might as well just leave them locked as long as you feel you might be needing 4wd at all. That way, all you have to do is to engage the transfer case shifter and you're good to go. You won't even have to get out again.
In extreme areas, many people just leave the hubs locked all winter and simply shift in and out of 4wd low or high as needed.
When in 4wd with the hubs locked, you need to be conscious of the road conditions. As it dries up and you're on hard pavement, kick it back into 2wd and only put it back in when you need the extra traction.
There is always going to be a naturally tendency to bind the driveline in 4wd. The front and rear differentials are very often running with just slightly different ratios (for example, 4.10 front and 4.11 rear). So on high-traction surfaces you should be in 2wd to avoid binding. In slipperier conditions, it doesn't matter because tires can always spin a little independently of each other.
On an AWD (all-wheel drive) vehicle, this effect, along with uneven traction funkiness, is minimized by there being another differential in the middle. Instead of a locked gear like you have in our transfer cases, there is some slip built in to the system so that you can run them at any speed on any surface. Most stay engaged all the time, and nowadays most (if not all) are computer controlled anyway, so may know better than you anyway, what to do about it all. ;D
And the last thing to consider with any full 4-wheel drive vehicle like this, is that unless you have some sort of traction aiding device (limited slip or locker) you may only have 1 wheel drive or 2 wheel drive. With open differentials, only one wheel is actually getting any power of note. With a limited slip or locker though, power is being fed to both wheels. Sometimes at different rates, sometimes equally (locker or spool).
The upside is more available traction. The downside is if you loose traction with both wheels on an icy surface, it can be more dangerous due to having both wheels wanting to spin equally. This usually pushes you sideways uncontrollably.
So see? It's not as simple and no-brainer-ish as one might think. It can aid in your journey, but there's always something else to think about.
After all... having 4-wheel drive just means you get stuck deeper and harder and farther away from help!
So while it's mostly good, there is some bad to keep in mind, covering your individual circumstances.
So, do you know if you have a traction aiding device in either of your diffs?
Paul
