Algodoo

A kind Reddit user explained how to script axles so that they can hold two objects together with the brake engaged but be stretched so that two objects can spin together but be in different spots, and using this knowledge I replaced the bulky and unstable springs and rods with axles. This doesn't make the vehicle faster unfortunately, and for some reason I had to make the "gears" in the gearbox heavier to transmit a usable amount of force from its output to the wheels so now it's very front-heavy (I kept the density of the payload the same), but I feel like it's a step in the right direction. The longer front suspension arm was another improvement. Same controls as the earlier model, 1 for first gear, 2 for second, 3 for third, and R for reverse.