Breakin Oil?

Messages
238
Location
Girard, Ill
I noticed from reading posts that with a new engine and the desire to use a fully synthetic oil that one should FIRST use a petroleum based oil for the first 5000 miles or so before switching to the Syn! However, new vettes come with Mobile 1 Syn from the factory and GM states that this completely satisfactory. Thoughts? I asked GM about this concern and they told me that first using a petroleum based oil is all bunk! Not needed!
 

Patman

Staff member
Messages
22,000
Location
Guelph, Ontario
You're safe, it's an old wives tale that engines can't run synthetic when new. Perhaps with old technology, but on modern engines the rings are fully seated very fast and you can safely run synthetic when new. Just look at how many Corvettes have come from the factory with synthetic in there, and have broken in perfectly fine. No worries! [Coffee] (if you're still worried, just give the car to me!) [Wink] [Razz]
 

Al

Messages
19,248
Location
Elizabethtown, Pa
There might be one exception. There are consistant reports that Honda does require a special (unknown formula supplied by them)oil for the first 5K miles I believe. That is very difficult for me to believe though. Still I can't prove it wrong-nor has anyone else been able to (that I know anyway). Also RedLine claims that you should not use their oil until the engine has 10K. That might be due to the fact that lots of racers who rebuild their engines frequently don't have the same technology and microfinishing techniques as the car manufactures. Also Redline is an ester. But, I also agree with Patman (for whatever its worth [Big Grin] ) I have used syn in several vehicles well before the 1000 mile mark. One had 30 miles on it.
 
Messages
922
Location
Ontario , Canada
Honda's special break in oil is just loaded with moly, that is their special additive. I swap that oil at 1500 miles usually. I believe most rings are fully seated within the first 100 miles, perhaps GM breaks their engines in on a bench before installing them in the car, who knows ?.
 

mdv

Messages
531
Location
MA
quote:
Originally posted by Al: There might be one exception.
Maybe two. Bill Miles (maxima spreadhseet) has noticed that Nissan VQ switched early tend to have higher wear rates than those that switched later in life. Granted, since the spreadsheet is a relatively small number of cars compared to those manufactured and the average member there is pretty hard on the car it might just be a coincidence. It certainly peaked my interest though.
 
Messages
344
Location
Rochester Hills, MI
Synthetic oils for new engine break-in is a hotly debated topic on this and other forums like miata.net & neons.org. Since most of the discussion revolves around anecdotal evidence and opinion rather than fact, I always use dino for 5 to 6K miles on my new cars and then switch to synthetic. Consider that Redine & Neo advise dino oil for break-in. I know that Corvettes,Porsche,Vipers and other high-end vehicles (I think Saturn used to come with synthetic factory fill)are delivered new with synthetic oil in the crankcase, but that is more for high engine temps rather than longevity. Until someone supplies hard evidence on this issue (preferably an OEM), why not be safe and use dino for a few thousand miles to properly break-on the engine. As long as your break-in dino is clean, I don't see any downside. Unseated piston rings is the risk if your particular vehicle needs something other than synthetic to break-in. Dino oil changes with a new filter around the first 1,000 miles, 3,000 miles and then a switch to synthetics at 6,000 miles should provide proper break-in while protecting your engine. [Cheers!]
 
Messages
903
Location
CA
quote:
Originally posted by harbor: Dino oil changes with a new filter around the first 1,000 miles, 3,000 miles and then a switch to synthetics at 6,000 miles should provide proper break-in while protecting your engine.
That's probably what I would do. In addition, RL is pretty expensive to dump at 1K,3K and 6K.
 

Patman

Staff member
Messages
22,000
Location
Guelph, Ontario
quote:
Originally posted by harbor: Until someone supplies hard evidence on this issue (preferably an OEM), why not be safe and use dino for a few thousand miles to properly break-on the engine. As long as your break-in dino is clean, I don't see any downside. Unseated piston rings is the risk if your particular vehicle needs something other than synthetic to break-in.
I usually do a couple of oil changes with dino on my new engines anyways, just so I'm not wasting expensive synthetic. But if I buy a car that already has synthetic in there, I might as well stick with it (such as if I'm lucky enough to get a new Corvette someday)
 
Messages
344
Location
Rochester Hills, MI
yankees1 - See attached thread from similar discussion on break-in oil from a different forum: Q: If break- in happens so quickly, why do you recommend using petroleum break- in oil for 1500 miles ?? A: Because while about 80% of the ring sealing takes place in the first hour of running the engine, the last 20% of the process takes a longer time. Street riding isn't a controlled environment, so most of the mileage may not be in "ring loading mode". Synthetic oil is so slippery that it actually "arrests" the break in process before the rings can seal completely. I've had a few customers who switched to synthetic oil too soon, and the rings never sealed properly no matter how hard they rode. Taking a new engine apart to re - ring it is the last thing anyone wants to do, so I recommend a lot of mileage before switching to synthetic. It's really a "better safe than sorry" situation. Q: My bike comes with synthetic oil from the factory, what should I do ?? A: Synthetic oil is so slippery that it actually "arrests" the ring sealing process before it's complete. The best power and least wear comes from perfectly sealed rings !! The solution is to change the factory installed synthetic oil back to petroleum for the break-in period. ----------------------------------------------------------- That comes from a bike site, but they noted at the beginning of the article that this applies to ALL 4-stroke engines, car, lawn mower, etc. That only confuses me more - I know "conventional wisdom" has always been to wait on the synth for at least a couple thousand miles, so what is different now that allows the Corvette, Viper, etc. to run it from the start??? [ 22. December 2002, 13:05: Message edited by: MX5
 

Patman

Staff member
Messages
22,000
Location
Guelph, Ontario
But the thing is, synthetic oil is not more slippery! If it were true, we'd see a big difference in wear metals on synthetic run engines compared to dino. But we don't.
 
Messages
903
Location
CA
quote:
Originally posted by Patman: But the thing is, synthetic oil is not more slippery! If it were true, we'd see a big difference in wear metals on synthetic run engines compared to dino. But we don't.
Hey wait a minute, Sometimes we see a car getting 450 hp versus 446 hp on a dyno test. [Roll Eyes]
 
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