I know what I would change it at but I would like to get some other opinions as to when it's a good time after break in to change to synthetic oil?
Thanks
Jim

Hi Jim -

I assume ring seal is what would hold most back from synthetic. It's my understanding that modern rings seat very quickly. I changed my oil & filter after initial fire-up and 10 miles of driving, and used dino oil just to be safe. I'll drain it after another 300 - 400 and switch to Mobil 1. This on the advice of my machinist.

Al

This is an evolving saga because the traditional myths of synthetics are going away with the education of the public about these lubricants.

There are many OEMs now (and Mercedes has been doing this for years) that are providing synthetics from the get-go. New Corvettes are one!

Anywho, micro-metalurgy is the key here. Machining processes are much better these days and tolerances are getting smaller and smaller. Most, if not all new OEM cars and trucks can be converted to REAL (group V and VI basestocks...such as Mobile One) almost immediately. If your engine is moderately crosshatched waiting for a few hundred miles is okay, but after 500 miles can be done.

I have started with synthetics in several engines with nary a problem No oil usage and everything seated up nicely, but all mine have been micro-honed!

Thinking (posting) out loud here. I have read litature about how it was normal practice to break aircraft engines in on mineral oil then change over to more slipery castor oil. This was done to give the parts a "chance to get to know each other" Getting to know each other sounds like polishing the high spots down to me!If everything in an engine is clearenced correctly, the right cross hatch hone pattern is there, done using the right grit stone so as not to chip any ring coating: then why would any wear be desireable??????? Maybe you start with cheaper oil because it is changed after a very short period to flush any dirt out?? Then go to the best lubricant you can get? If the parts never "break in" don't they remain new forever??
All IMHO
HG

Steve is right in his assesment there. Syns are best used after you break in the engine but if a good shop built it, not shade tree with old tools, you can dump the break in oil after 500 miles, change the filter at the same time and go for your 100% syn.
With engine rebuilds easily topping $2000 these days, why would anyone hesitate changing out in a short time and going to a quality syn?
Ive run them for over 25 years and they are better for your engine.

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