Dry vs lubed threads is one those highly controversial or contested topics.

In the end it's all about clamping force and that's what the gasket designers were looking for. The clamping force can not be measured in the field and back in the day torque on the fasteners was the best way to get the desired clamping force. Unfortunately the torque variables are very dependent on type of lube and friction and bolt strength and yield. For older vehicles most of the specs were dry torque spec.

Modern car use torque to yield bolts or angular torque, more info below:

http://wbtools.com.au/how-to-understand-angular-torque-and-torque-to-yield/

With certain lubes it is easy to break the bolts before the torque is reached under certain conditions, especially with used or stretched bolts. Several of the articles below will explain and measure the extra clamping force applied and the extra load on the bolts when the threads are lubed vs dry when torqued to the same value.

http://www.engineeringtoolbox.com/torque-lubrication-effects-d_1693.html

http://www.eng-tips.com/viewthread.cfm?qid=173061

http://www.intermotive.net/Tech%20Tip/Tech%20Tip%20-%20Jan%2008.pdf

http://www.automotiveforums.com/t903269-wet_torque_vs_dry_torque.html

http://forums.mtbr.com/tooltime/torque-dry-vs-lubed-716358.html

This one is specific to not using anti seize in their opinion

http://benmlee.com/4runner/threads/threads.htm

I lead off with this post saying it's controversial..............who's going to be the first to break off a head bolt ?

[img]https://volvoforums.com/forum/attac...ken-cylinder-head-bolt-block-step-8a.jpg[/img]


Last edited by showkey; 07/10/2017 9:57 PM.