Tanks travelling at 60mph are a complete fantasy, they can, same as they can jump over berms and kinfe edges at high speed, normally seen on the manufacturers sales video's. In RL tanks that are jumping ramps at speed would be rendered ineffective in short order, with optics and radio's etc being damaged, gunlaying calibration knocked to hell, not to mention the cut up and bruised crew.
At high speed the greatest threat to crew is the tracks snapping and coming off the rear pulley, and over the top, potentially decapitating the commander/operator. Coupled with the roll potential of a now one tracked high speed 56 tons of steel. Tracks strech considerably in normal use and the potential for pins snapping at speed precludes high speed use.
I'm guessing you have never driven a combat tank. I have only test experience in the Abrams but I got a lot of time driving the M60-A1 and the M-88 tank retriever, in the desert at higher than combat speeds...40-50 mph across the desert...never threw a track, never broke one, broke a torsion bar once when we rolled over a large boulder...a lot of tankers did break things, especially the dipstick reservists because they didn't know how to operate the things at high speeds.
None of my crew suffered an injury during our runs...and if you had a good driver, you could sit on top of the commander's cupola fairly easily.
The M1 Abrams is a much better tank and 45-55 mph off road...it has a very good suspension system...you have to really jerk it around off road to break or throw a track.
312BAR is just looking at the maximum
road speed...cross country speed was dependent on the terrain, and rarely exceeded 45 mph even in vehicles that could go that fast, nobody wanted to break down and take a chance on getting caught by the enemy...unless they were being fired on, then the basic rule was, get it in gear and move.