RTI stands for Ramp Travel Index. It quantifies how well a vehicle keeps all four wheels planted over uneven terrain by driving one wheel up a specialized angled ramp until another wheel lifts off the ground. The distance traveled up the ramp is divided by the vehicle's wheelbase and multiplied by 1,000 to generate the final score. Off-road builders use this metric to evaluate suspension setups, where higher scores indicate superior axle articulation and better traction on severe trails.
We backed the rig onto the 20-degree ramp and measured an RTI of 820 before the rear tire lifted.
A score of 1,000 means the vehicle traveled its entire wheelbase length up the ramp without lifting a tire, which is a common benchmark for dedicated rock crawlers.