Telehandlers are heavy duty work machinery made specifically to work in rough terrain. This however, does not mean they can be driven without regard on rough terrain. These types of machines have a a lot 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 equipment while also keeping the load low. Downshift to 4WD and a lower gear, prior to getting on the slope. Using the engine brake will help to control the telehandler's speed. Try to avoid turning on a slope if possible. If you must make the turn, use extreme care and take it as wide as possible.
Under any circumstances, do not drive across extremely steep slopes. Descend and ascend slopes with the telehandler's heavy end pointing up the incline. Even when there is no load on the forks, the machine's counterweighted rear is fairly heavy; hence, it could be required to drive backwards up slopes. Once the telehandler is carrying a cargo, the front of the unit becomes the heavy end, and you can back the machine down the slopes.
Operator training is hugely essential on a mixed jobsite. Rear pivot equipment would usually operate on the same jobsite of coordinated steering equipment, where everybody is allowed to use all of the equipment. In this case, an individual who is used to using a coordinated steer machinery can jump onto a rear-pivot machine. A really key difference between how these two units work has a lot to do with what part of the machinery extends outside of the turning radius.