what speed 5/6 gear towing 12000lb 5er?
You should never tow anything faster than 60 mph, ideally it should be 55 mph, as far as gearing goes you should never be in an overdrive gear while towing, so check your specs and find out what gear is your 1 to 1 ratio, most trucks it is 4th gear that has that ratio. So slow down, save your equipment from premature failure, and possibly your life.
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