Long Drives to Offset Short Trip Use

blupupher

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My beater is short tripped all the time by the end of the winter you take the oil cap off the engine it has all white stuff on it condensation
Similar here:
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The picture is from my '02 F150 after 5000 miles/10 months. Lots of short trips (6 miles round trip for work, 3 days a week), but I was doing a 100 mile trip to my moms once a month or so. This pic was take the day after I had done the 100 mile trip.
Oil on dipstick looked fine, but the long oil fill tube where the cap sits apparently does not get hot enough to get the moisture off the cap.
I wiped it off and did not see any more for the next 2 months when the oil was changed.
I have yet to see this again in the past 4 years.

Maybe in the old carburetor days this was a thing, but I see no reason to do it with a modern car.
You still can get moisture in the oil with modern vehicles. And GDI is notorious for getting fuel in the oil.

Making up for short trips is like trying to make up for lost sleep by sleeping longer the next night. I don’t think it works that way. The damage, if any, is done and will stay done.

A long trip certainly can evaporate water from oil if the oil gets hot enough for a long enough time. An oil temp of 212 for a couple of minutes isn’t going to evaporate squat.
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It is not the same as making up for sleep.
If you short trip, the oil just does not get hot enough to evaporate the moisture and fuel in the oil.
Getting it up to temp and keeping it there will allow much of the trapped moisture and fuel to evaporate out.
Yes the oil quality had degraded some due to the buildup, no you will not get 100% of it out, yes there are other products of combustion that are still in the oil, but getting the excess moisture and fuel dilution it out will help keep it from degrading as fast as if it were sitting in there, as well as keep the oil from getting so much moisture built up into it that it turns into mayonnaise.
 
Joined
Jan 9, 2016
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Cheshire, England
If the car is parked in a garage, remove the oil cap and let the engine breath overnight. The moisture and the mayo will evaporate off even if the oil isn't fully up to temperature.

I did this for 14 years of riding a motorcycle through the winter. Being an air cooled BMW it was over cooled in the winter and the oil temperature wouldn't fully come up on my daily commute. Mayo would form in the oil filler and inside the valve covers before I decided to let the thing breath after every trip. It's the work of a few seconds to undo the dipstick on a bike and I appreciate it's a lot more hassle on a car but it really does work. You might be surprised that mayo turns back to oil but it does if you let it breath after every trip. If you let it build up over time then of course it won't.
 
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Lake Havasu City, Arizona
This all revolves around getting the oil above 212 F, and keeping it there long enough to evaporate, or "boil off" any moisture and condensation that has accumulated inside the engine. This is harder to do in the Winter in the Midwest, than it is in the Southwest in the Summer months.

Also, as was mentioned, areas with a high relative humidity are far more prone to this problem. Unless your vehicle has an oil temperature gauge, you are simply guessing if your oil is hot enough. Short trips in cold, wet, humid climates are the worst for this to occur. Unless the engine is operated at a higher RPM under a load, for a longer period of time, the oil temp most likely will never get hot enough.

The only solution to driving short distances in cold weather, is far more frequent oil and filter changes. Otherwise, enjoy the Mayonnaise.
 
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on the road in NE Oklahoma
I suppose all engines are different, and do expect some oil warm-up time differences between iron and aluminum engines.

On my ‘02 Jaguar XKR I have oil and coolant temperatures monitoring via the OBD-II port and an aftermarket gauge plugged into it permanently. Yes, OCD at its worst.

So anecdotally I can report that for my aluminum 4.0 L engine, the oil temp gets warmer faster than the coolant until about 140 F. Then they rise about evenly until the thermostat opens at 184 F. Then the oil temp keeps going up until it’s about 16-18 degrees F higher than the coolant temperature.

On most days the coolant is about 185-195 F with the oil temp not quite 20 F higher. In the summer with ambient air temps of 95-115 F the coolant is up to 220 F (unless I’m stopped in traffic) with a corresponding oil temp of 136-138 F.

In my view Jaguar was stingy with the size of the air intake opening (for the radiator), so the car will cool better at speeds over 80 mph when the airflow is optimal by about 5-10 degrees in the summertime.


Z
 
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Nov 11, 2018
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Great Lakes
And where does the air come from for combustion? :unsure: That's right ;)
This is a bit simplified but in perfect conditions burning 2 molecules of pure octane with 25 molecules of oxygen nets 18 molecules of water. You can have exactly 0 moisture in the air, but the exhaust will definitely have some.
2C8H18+25O2=16CO2+18H20
 
Joined
Jan 21, 2011
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Location
California
I would only bother with a long drive for "oil cleansing" if the usage is an extreme example of short tripping. Then I'd simply take the long way on a drive I'd be taking anyway, not a special trip just to drive. Considering the cost of fuel nowadays, you might be better off just short changing the oil!
 
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