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YOUR RESEARCHRebuilt Engine- Reason to NOT use break-in oil?
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Use against you later
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Follow what your rebuilder suggests and it can't be used against you later.
Leading evidence: 'Use against you later' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace oil' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Performed · outcome unconfirmed
I use a ZDDP additive in the first batch of oil after a rebuild of an engine.
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Suggestion · Original poster
The break-in instructions that I received only advised that I change the oil after 1,500 miles and keep the revs below 4,000RPM during this period.
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Suggestion · Original poster
Should I use the 5W-30 or 10W-40 break in oil, before switching to 5W-40 synthetic for regular use?
Use break-in oil, i was told this is not necessary
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Suggestion · Original poster
When I asked about using a break-in oil, I was told this is not necessary.
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Rennlist: 1 discussions
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After months of waiting, I finally received my rebuilt engine for my '99 3.4L 996. It is a bit of a "budget" rebuild from a company known to have been rebuilding M96 motors for many years. Nothing fancy. Basically the engine has received new steel cylinder sleeves and new piston rings as well as all new bearings, seals, timing components, etc. The crank, pistons, rods, and valves are re-used. I will be installing the engine this weekend and hoping to get it fired up by Christmas.
The break-in instructions that I received only advised that I change the oil after 1,500 miles and keep the revs below 4,000RPM during this period. The engine builder advises using Mobil1 or similar oil. When I asked about using a break-in oil, I was told this is not necessary.
My question: Is there any reason to NOT use a break-in oil for the first 500 miles or so? Could it potentially cause any harm? Why would the engine builder not recommend it? Is it because the engine has steel sleeves as opposed to honed cylinder walls? I'm leaning toward using Driven BR conventional break-in oil and then switching to Driven synthetic 5W-40 for the life of the engine.
Secondary question: I see that Driven does not offer a break-in oil in the 5W-40 weight that I would like to use for the life of the engine. Should I use the 5W-30 or 10W-40 break in oil, before switching to 5W-40 synthetic for regular use?
I'm planning on calling Driven tomorrow for some advice, but would like to get some hopefully un-biased feedback here as well.
Thanks.
I think many here will be afraid to reply because any answer COULD be costly to you
personally i would do as the builders request this way you have some recourse
I am guessing you could do that, but to the best of my knowledge, Porsche doesn't put in anything special on their new cars. I believe your car came new with Mobil 1 from the factory.
Do what the builder says. I just had mine rebuilt with steel sleeves and the builder did put in break-in oil for the first 1,000 miles. I was advised it would use oil and to not add any additional oil if it got low. So each builder is different in their methodology. I would heed their instructions.
