I had an anxious moment 3 years back returning from LA heading North on the #5 just past the Bakersfield off ramps, seen a big rig leave the divided hwy coming toward me at high rate of speed, much dust n weeds being flung up, rig stayed upright and stayed straight down the divide. Very sandy area, tumbleweed n sage brush landscape, smooth level and firm bottom, no time to find out what happened as we were barreling toward San Fran, rig barreling toward LA, trajectory of the rig could have been an intercept for us but the driver straightened er and held on, rig stayed upright at least until it disappeared from my rearview in a cloud of dust. From the quickest of glances I had it appeared the left front tire blew out or broke down off the rim, only speculation though on my part, had only split second to access the situation.