[HWYSTR455]

Just to say it out loud, the lubricant in assembly lube stays on the surface for some time, even if the 'carrier' gets almost immediately washed away. So thinking that it doesn't have an impact more than the fractions of a min oil reaches the assembly lube is incorrect.

What's the factor that causes the most engine wear? Initial startup. And that's through the life of the engine, not just the first startup.

Do you fill the oil filter when you do an oil change? Based on some mentalities, some would say it's not needed. Does it impact the life of an engine? It could make the difference between an engine that goes 100k miles and an engine that goes 300k miles. Same principal applies to assembly lube.

In almost every situation, there will be 'foreign matter' in a newly assembles engine. It might be fine enough of a material that won't cause immediate damage but can reduce the potential life of an engine (100k/300k).

If someone wants to avoid spending $10 on a bottle of assembly lube and just use oil or whatever, so be it, but can't deny there is no impact or risk.

STP as discussed here is an additive, and technically not a lubricant, also just to say it out loud. It may have some lubricants/properties in it, but not anywhere near what an assembly lube has. And because of how thick it is, it can actually prevent the lubricant properties of engine oil from reaching the surface.

'Professional' engine builders use assembly lubricants, 'general' mechanics in the field usually don't. Does it make a difference? You be the judge.


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