Telehandlers are machinery which are meant to operate in rough environment, however, that doesn't mean that they can be driven without any consideration for the environment. These types of machinery have a much greater risk of load loss or tipping over when they are traveling on slopes.
When traveling on a slope, make certain that you move slowly with the machinery while also keeping the load low. Downshift to 4WD and a lower gear, before getting on the slope. Using the engine brake would actually help to control the telehandler's speed. Try not to turn on a slope if possible. If you must make the turn, take it as wide as possible and use extreme caution.
Under any conditions, do not drive across extremely steep slopes. Ascend and descend slopes with the telehandler's heavy end pointing up the incline. Even when there is no load on the forks, the counterweighted rear of the machinery is quite heavy; hence, it could be required to drive backwards up slopes. Once the telehandler is carrying a load, the front of the unit becomes the heavy end, and you would be able to back the machine down the slopes.
On a mixed jobsite, operator training is really essential. The coordinated steering equipment, along with the rear-pivot equipment often operate on the same jobsite where everyone is permitted to operate all of the machines. In this instance, an individual who is used to utilizing a coordinated steer machine could jump onto a rear-pivot machine. A really key distinction between how these two units work has much to do with which part of the equipment extends outside of the turning radius.