The Mach2 is approved for general Off Road use.
This being said, proper caution is always required. We call this common sense coverage.
Drive slowly and carefully in all off-road situations. If you are driving too fast and hit a big bump that causes damage to your rack or vehicle, that is not covered under warranty. If you are using the rack on demanding 4×4 terrain and drop off a ledge and bash the rack, this is not covered by warranty.