TM  1-1  500-204-23-2 Table 4-5. Torque Values for MS21921 Coupling Nut Based on Lubrication Method, or Dry (Lubrication- None) as Directed in Applications Column and Appropriate Lubricant Column, Table 4-6. Alum  (6061-T6)  tubing Tube Code¹ wail   thickness   (in) Torque  (lb  in.) heavy thin min. max. -2 -2 -2 A,  B -2 -3 C -3 -3 A,  B -3 -4 C -4 D -4 A,  B -4 -5 -5 -5 A,  B -5 -6 C -6 D -6 A,  B -6 -8 C -8 D -8 D -8 A,  B -10 C -10 D -10 D -10 A,  B -12 C -12 D -12 D -12 A,  B -16 C -16 D -16 A,  B See  footnotes  at  end  of  table. 0.028 95 105 0.035 0.028 0.049 0.028 0.065 0.035 0.049 0.083 0.035 0.049 0.095 0.049 0.065 0.065 0.049 50 60 95 135 120 135 170 215 245 190 215 215 245 470 510 340 380 340 380 470 510 620 680 380 450 380 450 620 680 855 945 400 470 400 470 855 945 1140 1260 750 850 1140 1260 105 145 135 145 190 Change 3 4-21