Telehandlers are machines that are designed to operate in rough terrain, however, that doesn't mean that they can be driven without any consideration for the environment. These types of equipments have a a lot bigger risk of tipping over or load loss when they are traveling on slopes.
When traveling on a slope, make sure that you move slowly with the equipment while also keeping the load low. Downshift to 4WD and a lower gear, prior to getting on the slope. Using the engine brake would help to control the speed of the telehandlers. Try to avoid turning on a slope if possible. If you need to make the turn, use extreme care and take it as wide as possible.
Under any conditions, avoid driving across extremely steep slopes. Ascend and descend slopes with the telehandler's heavy end pointing up the incline. Even when the forks have no cargo, the machine's counterweighted rear is quite heavy; hence, it can be necessary to drive in reverse up slopes. When the telehandler is carrying a cargo, the front of the unit becomes the heavy end, and you will be able to back the machinery down the slopes.
On a mixed jobsite, operator training is really important. The coordinated steering equipment, along with the rear-pivot machines often work on the same jobsite where everyone is permitted to operate all of the machinery. In this case, a person who is used to using a coordinated steer machinery can jump onto a rear-pivot equipment. A really significant difference between how these two units work has much to do with which part of the machinery extends outside of the turning radius.