the larger "Modified" power cap modules are the way to go

Item 15350 Rev-Tuned Motor PRO

You will instantly feel the power and precision that have made Caterpillar the world's largest and most respected name in earthmoving

Weight: 200g (excluding servo horn)

Toe-in: Front adjustable with tie rod

Power Hobby - 110mm Promatics Two Stage Internal Spring Shocks, Green, 2 Shocks HPI115984 the larger "Modified" power capFeatures: Bleeder hole Machined aluminum shock bodies Scale internal spring design Triple o ring cartridge Includes additional option springs to tune the spring rate ( soft Medium ) Allows you to set up the shocks with a sprung or droop configuration Fits 1 10 Crawler