w350 dually brake rotor bolt torque spec

[comotionman]

i am putting new rotors on my truck and need the torque spec for the bolts that hold the rotor on the hub. they are 9/16 bolts. also would like to know the lug nut torque spec. someone on another board said lug nuts should torque to 300lbft. could that be right? a quick google search showed sae torque rating for 5/8-18 grade8 is 215lbft. thoughts?

[dpuckett]

Cant help you on the rotor to hub spec, but I know from personal experience that anything less than 300ft-lbs is asking for the lug nuts to back off. BTDT, on interstate across central Arkansas. Danged near gave myself a hernia tightening the rest of them up with only a 18" crapsman breaker bar.

DP

[RumbleFish]

i seem to remember seeig 325ft-lbs as the spec for the lug nuts somewhere, maybe in one of the owners manuals or something. if i stumble across my fsm ill look up the drw adapter to rotor torque spec, as im curious myself.

[comotionman]

i hear you on the craftsman 1/2" breaker bar. i broke two of them just trying to loosen the lug nuts. could not even break a lug nut loose without falling apart. that was before i had any idea that the torque spec on the lugs is 300-350ftlb. well i had to run to harbor freight and get a cheapo 3/4" breaker bar. that got the lugs loose so i could remove a wheel for inspection and get started on the work. i did put the wheel back with the 3/4" breaker without knowing at the time of the factory torque spec requirements for the lugs. i drove it about 400 miles through some fairly serious mountains pulling a trailer with a decent load in truck and trailer. lucky i did not loose a wheel i guess. that was also before i know about the tsb about wheel centering. i lucked out there too as it was pretty smooth rolling. are you aware of the tsb? the wheels are neither hub or lug centric. anyway i scored a nice 3/4" drive torque wrench on ebay. so i can properly torque the lugs. i will just go with sae torque spec on the rotor bolts based on size and pitch. thanks.