If they are 1/2"-20 fine thread, trailer wheel studs are often grade 8 studs. And if so then 120 ft lbs is max recommended for the stud.
On my steel wheels, I use 110 ft lb. And for sure after you change a tire, after 50, 100 and 150 to 200 miles check the lug nuts again. That first 50 miler is really important, odds are good some of them will take more torque. This is just the way lug centric wheels are. Since there is no hub pilot in the center to take the rolling load like in auto's, the lug nuts take the load and the bevel on the nuts and wheels have to seat right to stop the movement.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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