Topic: break-in oil
in Forum: C3 Engines
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Lifetime MemberDeBerry, TX - USA
Joined: 2/27/2002
Posts: 1006
Vette(s): 1971 383 Stroker- mille miglia red...5 speed
What's considered the best weight break-in oil and how long before you change it....to what
I know the voices aren't real, but they have some pretty cool ideas... 
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Frederick, MD - USA
Joined: 9/8/2003
Posts: 3398
Vette(s): 1969 convertible L71 427/435 4-speed black interior
Ask the engine manufacturer or rebuilder. It's likely a 5W-20 or 5W-30 oil (maybe a non-synthetic). Run it for 1000 miles than change it to whatever best suits the temperatures you plan on driving in or whatever the manufacturer recommends.
Once the engine is broken in, you can use a synthetic or synthetic blend as well as a pure petroleum base oil, but it's your choice unless you get specific recommendations from the engine builder to the contrary.
Once the engine is broken in, you can use a synthetic or synthetic blend as well as a pure petroleum base oil, but it's your choice unless you get specific recommendations from the engine builder to the contrary.
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Duncanville, TX - USA
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Member: NCRS, NCRS Texas, Corvette Legends of Texas
Sounds gud to me. 
Joel Adams
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On my new engine, the builder said use Rotella-T 10 W 40 for 500 miles,
then change out oil and filter and go with whatever you want. I
went with Castrol Synthetic and a racing filter.
He said it is due to the fact that the new oils, synthetic and non-s don't have the sulfer and other stuff you really need to seat the rings and stuff.
I'm only reporting what he said. I will tell you that she runs GREAT (except I still need to hear from the #$)%*($*&
Insurance company to fix her).
He said it is due to the fact that the new oils, synthetic and non-s don't have the sulfer and other stuff you really need to seat the rings and stuff.
I'm only reporting what he said. I will tell you that she runs GREAT (except I still need to hear from the #$)%*($*&
Insurance company to fix her).
Lifetime MemberDeBerry, TX - USA
Joined: 2/27/2002
Posts: 1006
Vette(s): 1971 383 Stroker- mille miglia red...5 speed
HMMMM. They put Pennzoil 30w in it and said to run it for the first 1500 miles. Sounded kinda heavy to me, especially this time of year. They said it would help seat the rings. Ya'lls advice sounds better to me
Ya'lls advice sounds better to me I know the voices aren't real, but they have some pretty cool ideas...
The guy who built mine is a race engine builder and builds his own race
engines. He seems to win a lot at the local tracks, so I took his
advice. Seems to have worked. He also said don't go over
2000 RPM's for the 1st 500 miles.
Just my thoughts.
Everytime I buy new vehicle/s at dearlership/s. They don't say anything on this '500 mile Oil Change' nor does the vehicle warrenty booklet. They only tell you about the 3,000 mile oil change. Why is that?
And when I went to the GM Corvette Assembly Plant in Bowling Green,Ky. I see them run very hard on the engines before they are even drive out of the Plant. That damages the engines. Yes or No? Shouldn't the vehilce companies tell the buyers on this 500 mile oil change and/or change the oil themselves after there engine runs??
To me it dependes on where you live and which way you use your vehicle to determain your oil. ??
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Willow Grove, PA - USA
Joined: 10/27/2006
Posts: 232
Vette(s): 1974 Stingray Coupe LS4 454 Dark Brown Metallic with Deluxe Saddle interior
wht I have always been told / taught
on rebuilt / new engines fill with 10w30 and a bottle of GM EOS ( Engine Oil Suppliment) which can be had at most GM dealers.... EOS is to be used only for new / rebuilt engines, it is not a oil additive to be regularly used....
run that for the first 500 miles, then change the oil and filter, then another fill of 10w30 without the EOS...... drive that for the next 1,000 miles, drain and change, then do your oil changes as miles / or in use time requires.
Another thought.
If the engine does break in this time frame of 3,000 miles. It's still under warranty. So why do this??? Wouldn't the warranty cover this problem?? Say by these companies that make engines/rebuilds.
And to whom say to do this 500 oil change. Why isn't this in all the automobiles booklet? Does this help in a way the engine will not break within those 500 to 3,000 miles and having the automobile companies do an engine run? If not, why have a warranty?
I'll see what the Mythbusters have to say on this?
Lifetime MemberJoined: 9/8/2005
Posts: 241
Vette(s): 1980 with a Banks Twin Turbo
1969 Convert Big Block
1996 Grand Sport Convert
When I rebuild an Engine I change it at 100 Miles. When most People Rebuild a Engine they tend to Use a Lot of Assembly Lube on the Cam and Lifters that is not done at the Factory. This all gets washed into the Oil on Startup and by Changing the oil You get Ride of it. Also When Draining the Oil right away You are getting any Dirt that was Missed when assambly was going on. If something is going amiss in the Bearings You might spot it in the Oil before You Ruin Your Crank. Cutting the Oil Filter Open will show this better. If GM said to change the Oil at 500 and no other manufacture did it would make the Headlines that GM makes Bad Engines. Keep in Mind that the recomendations made are to make sure Your new Engine lasts at least as long as the Waranty Period and Not forever. If it lasted forever we would never buy a new one again. Richard....
in Forum: C3 Engines
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