Ok in the RC drift scene locking your diff usually consists of jamming your differential full of JBWeld and making it a heavy rock like item. Great way to waste power and make things hotter. I have researching mods and upgrades for my Tamiya CC-01 and discovered the scaler crowd have found a much better way of locking their diffs. I haven't tried it yet but I'm willing to bet this will work in just about any gear diffs with three spider gears. Look and learn.