Break-in oil - recommendations

Randy V

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If it is a roller cam engineI would just use Mobil1 5w30.
Flat tappet cam, I would use 30w Joe Gibbs...
 

Randy V

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GM has an excellent break-in additive you can pick up at the dealer for newly rebuilt engines.

You’re probably talking about GM-EOS.... I’ve not seen it in quite a while but it may still be available... As I recall it was a Moly-Zinc based product..
 

Randy V

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Wow... $27 a pint is a bit more than the $6 I used to pay at the Chevy dealer....
 
What engine are we talking about ???

For sure a proper fresh build crate engine comes with break in oil recomendations. That has to do with warranty.

Lingo is ZDDP and you want loads of it ( 1600ppm minimum )

After the first 300mile break in, oil + filter change to same spec.
After the second 300 mile break in, oil change + filter to engine spec.

Cam Shield is a good ZDDP suplement.
 
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