A couple years ago I bought a 6:1 torque multiplier. Didn't really need it and haven't used it yet but thought eventually it could be used on really tight big fasteners like a pinion nut, crank bolt, or axel nut. It was made by Wright tool company and with 200ftlb on the 1/2in drive input, you get 1200ftlb on the 3/4 drive output. It also has a conversion chart to use a torque wrench and a degree wheel. They are like $1200 new and I bought it used for $350 and can always get my money back out of it.