Torque Specs for Installing Demco 10 Inch Trailer Brakes and for Trailer Wheel Lug Nuts

Updated 06/13/2016 | Published 06/10/2016

Question:

Hello, I purchased the Demco Hydraulic Drum Brake Assembly - Free Backing - Galvanized - 10inch left and right hand assemblies as replacements for the old brake assemblies on my trailer. I have not been able to find the torque specifications for the 4 mounting bolts. Can you please advise what those torques should be? Also, the wheels for this trailer use 5 nuts on a 4.5inch bolt center. Can you also advise what the torques on those nuts should be? Thanks

asked by: Steven D

Helpful Expert Reply:

The torque value of the bolts/nuts used to hold the brake assemblies to the trailer brake mounting flange is going to depend on the grade of the 7/16 inch bolts you are using. The minimum for ASTM A307A Grade A hardware with 20 threads per inch is 18 foot pounds. But an SAE J429 Grade 5 goes up to 55 foot pounds.

Grade 5 hardware will have 3 lines on the bolt head point towards the middle. The A307A will sate A307A. If you aren't sure what you have send me a picture and I can determine what it is and the torque value.

The lug nut torque also depends on the size but also on the design of the nuts and the material of the wheel. I have included a picture that is a chart with lug nut torque values in it for oyu.

expert reply by: Michael H