Hello,
The subframe mount bolts are a much larger diameter. I fear you will snap these at 72lbs. You need to get a feel for these kind of things. These are non critical hardware, so specs may not be listed for such items. You can find a standard torque table for hardware which will give the torque specs for different hardware according to diameter and hardness. The numbers on each bolt head are the hardness of the fastner. Mercedes stndard hardware is "8g" which is a high strength steel (equivalent to grade 5 SAE). Use this 8g spec on these unmarked studs. Your motor mount support studs are 10mm diameter. Just look up the specs on the chart! If you have not yet developed a feel for tightening things, keep a copy of a torque chart handy for unspecified bolt torques.
Hardware used on such things as flywheels, or headbolts are much harder and may carry a rating of 10g or 12g. Torque specs should be followed closely when listed. Secial "stretch bolts" require a torque then an additional turn of a specified degree! Te stretch action of the bolt locks it into place and provides more lasting tightness with the abiltity to take up some slack.
Now if I can just find my torque table!? I am sure you can find one on line. I will get back asap.
Joe Alexander
Blacklick, Ohio
