99 boxster clutch

[JFP in PA]

Originally Posted by Boxstard

I hope you agree potential risk with lube and torque down to the spec. originally meant for dry where clamp force may get close to or exceed yield strength of materials. Do you lube every situation calling for certain torque spec, regardless?

No, I do not agree that there is a risk of over torqueing a given fastener because it is lubricated. In over four decades of lubricating fasteners prior to torqueing, I cannot say that I have ever seen one fail as the result. I would agree that there is a significant risk of under torqueing a fastener because it was assembled dry, causing the drag of the dry thread surfaces to be interpreted as the correct torque value.

And yes, we lubricate every torqued fastener. And in all the years I have been doing this, I have NEVER encountered a spec that specified dry rather than lubricated torque ( or the other way around) by any manufacturer. They simply give a torque spec or range, expecting the tech to be sure all the treads are clean and move freely in order to achieve the desired clamping force.

[JFP in PA]

Originally Posted by BYprodriver

ARP supplies their own lubricant with the bolts they make & sell.

Other companies sell similar products as well.

[Boxstard]

Originally Posted by JFP in PA

No, I do not agree that there is a risk of over torqueing a given fastener because it is lubricated. In over four decades of lubricating fasteners prior to torqueing, I cannot say that I have ever seen one fail as the result. I would agree that there is a significant risk of under torqueing a fastener because it was assembled dry, causing the drag of the dry thread surfaces to be interpreted as the correct torque value.

And yes, we lubricate every torqued fastener. And in all the years I have been doing this, I have NEVER encountered a spec that specified dry rather than lubricated torque ( or the other way around) by any manufacturer. They simply give a torque spec or range, expecting the tech to be sure all the treads are clean and move freely in order to achieve the desired clamping force.

Thanks or following through and sharing decades of experience.

My mindset is (was) that the torque spec is based on dry unless the manual/ procedure specifically calls for lubing the fastner (like locktite or threat sealer that may be called out for certain bolts), not mentioning some common sense that threads need to be clean and in good shape without causing extra friction and resulting in under-torque.

Obviously you think otherwise, more like lube is given unless OEM explicitly says not to lube for the given torque spec.

I just showed one example below, 718 manual specifying 'no grease' to wheel bolts to tighten to the specific torque, and I'm not splitting hair between grease and anti-seize here; they are lubricant.

You may be right that you have less risk to torque to the spec. with lube, if it is not clear that the torque spec is based on dry or lube. As mentioned before, I'm sure that components are designed with enough safety margin to take extra load, and probably it takes tons to actually tighten a faster to cause stress over material yield without feeling something is going wrong, starting to strip the bolt head or thread...

I'm not a professional mechanic, just an enthusiast with engineering degree and wrenching personal cars for 3 decades... not a P car (yet) but rebuilt 2003 Saab 9-5 engine from a bare block too that has 80K miles and counting, and never had issues of fasteners came lose so I can't be that bad