Revo & Summit’s linkage based suspension requires different push rod assemblies depending upon which rockers are used. Strong, 7075-T6 aluminum versions of each are available to decrease the total weight of the truck by 31 grams. Rod ends are already installed making it simple to just bolt them on the truck. When using progressive-2 rockers, spacers (part # 5133) are required for use with the 5318 or 5318X push rods. These spacers are included with the progressive-2 rockers.