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Discussion Starter · #1 ·
read a few times here recently that short trips can cause diesel to seep into the oil and dilute it. Im curious as to how this happens. why are short trips causing this and not a long trip? if this has something to do with a cold engine then why would it not happen during every cold start up, even if its a long trip you would still be starting off on a cold engine. any insight that would help me understand this would be appreciated
 

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Still kickin
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I could be wrong but my understanding is that it will have a little fuel dilution every time you start the truck. The reason short trips are so bad are for a couple of reasons.

First, you always get more dilution when the engine is cold because a) the rings don't seal as good when they're cold as they do when hot, and b) any fuel that might have leaked out of the injector while the truck is off will seep past the rings.

The second reason is the amount of trips during oil changes if you drive 5 miles a trip, you'll have 1000 cold starts in a 5k oil change. If you drive 50 miles then you'll only have 100 cold starts. If a certain amount of fuel is pushed past the rings on every start, at 5k you'll have 10 times as much fuel at 5 miles than you would with 50 miles. Make sense?
 

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Discussion Starter · #4 ·
yes makes sense, So it does happen with every cold start as i suspected.

anyone else have a take on this ??
 

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Injectors leaking. If your engine oil level is rising, it could be one or some of your injectors is leaking. My oil level has stayed the same/consistant since I had injectors replaced way back. But as Flopster said already, I agree also, but an oil analysis done by say Blackstone labs would tell you more.
 

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Discussion Starter · #6 ·
my oil level is fine. Im only asking because ive seen a few statements saying that short trips can cause fuel to get into your oil . i was curious how? I dont take short trips either , just curious
 

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Got Torque?
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I agree with Flopster. I think it is primarily item 2. All trucks go through this as the various metal surfaces tighten up (expansion). At some point, they seal fairly well (still not perfect), and no significant amount of fuel gets past the rings.

Another compounding factor for short-trippers (remember day tripper? now I wonder how many of you whipper snappers remember that song) is that while the engine is cold, it is more prone to damage, which can further increase oil leakage.

But overall, I think Flopster hit it right on the head.

Ralph
 
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