Wow.
See, this is something I didn't know. I always thought it was based on the items you were bolting together (and it kind of is), but didn't put the 2+2 together that they used specific bolts when engineering it, and the torque was based on the bolt used (which the engineers hopefully did all the math for).
Some engineer at some point did the math and decided that 6 grade 5 bolts, torqued to 30ish FT-LB is all that is needed to handle whatever load the transmission to block requires (hopefully without shaking loose). If the bolt is torqued to 31 FT-LB, then the clamping force of a 3/8 - 16 Bolt is between 480-560 LBS (depending on if the bolt is lubed or not) at each bolt. Assuming I put all the right numbers into the calculator.
Bolt Torque, Axial Clamp Force, Bolt Diameter Calculator | Engineers Edge
If you follow the 80LB Torque from the guide you are putting between 1333 and 1666 LBs of clamping force on each bolt, which seems excessive for an aluminum case.
You would have to put 396 FT-LB of torque on a 3/8 - 16 Grade 5 Bolt for it to deform...but, I'm sure the transmission housing would crack way before then.
There is the potential that I'm totally wrong and didn't understand this (math isn't my strong suit).
It doesn't really matter at the end of the day, but I just like to try to understand the "why" of things.
Ultimately as
@cucvrus said...just make sure they are tight