How would you define a "long trip" vs. a "short trip" for oil changes and such?


#1

This came up as a discussion the other day. I live about 10 miles from town and drive about 55-60 mph the whole way there so the engine gets nice and warm and stays warm for most of the trip. I view this as a long trip as everything gets warmed up and any moisture should be blown out through the PCV and not accumulate in the oil. Now, I have a friend who sees a long trip as something a half hour or more away. I view it as the engine simply getting up to operating temp and staying there a while.

Now for the short trip. I have a neighbor that lives 1/4 mile from me. I sometimes drive up for dinner and sometimes walk. I view these drives as a short trip as the engine barely runs at all to get there and doesn’t even start to warm up. I am sure this isn’t good for things at all as I usually do this twice in one day when it happens. Now, lets say I am coming in from town and stop there first for a minute and then go on home. Sure, the car is turned off for a bit and then restarted and run for another 1/4 mile but I view this as part of the same “long trip” since the engine is still nice and warm.

I want to hear what others think about this situation and if simply getting the engine warm for 10 miles or so is considered a long trip.


#2

I agree with your opinion. I work 12.5 miles away, but use city streets with lots of stop signs and lights. It routinely takes me 30 mins a leg. Even if I make a short stop, I view it as part of the long trip, since the engine remains warm. I used to work about half a mile from work. The trip was so short, the heater would not be warm when I got there. But, as long as I took it out for longer drives, which was frequently, I didn’t worry about bad effects.


#3

You have the right idea. The key factor here is to warm the engine up thoroughly to drive off water vapor and any liquid hydrocarbons by vaporization. This pevents sludge formation and excessive engine wear.

My late father-in-law did not like the way the paper boy delivered his morning paper. So each morning he started up his V8 Mercury Marquis, which was parked outside without a block heater to prewarm the car, and drove 0.5 miles to the nearest 7-11 and bought the paper there.

I tried tactfully to point out that a subscription was cheaper than buying individual papers, and that oil and car companies used his driving style, called the Àunt Minnie Test` to determine how car behaved during the most extreme punishment you can give it.

Although he was an Air Force veteran and familiar with cold weather starting problems, the advice fell on deaf ears.

Most owners manuals clearly define what constitutessevere`drivning conditions.


#4

From a technical standpoint, I agree with you definitions.
From a personal standpoint, I think if a “long trip” as being one that requires an overnight, and a “short trip” as being any trip that does not. Even if that “short trip” is 250 miles total, which I often do on a nice day just to explore an area that I haven’t explored before.


#5

Gotcha! I am sure this also matters for the vehicle being driven. I have three different vehicles and all take a different amount of time to warm up. The 1994 Geo Metro uses a 1.0L 3 cylinder engine with an aluminum block. This thing is practically warmed up by the time I get to the main road. The heater is nice and warm and everything. The only time this takes longer to warm up is when it is REALLY cold outside like it was this winter. There were a few times where it seemed like I was halfway to town or more before it was nice and hot.

The 2000 Chevy S-10 4.3L with a cast iron block seems to take practically all the way to town to warm up. The good news is that this gets a good long trip at least once a month where it warms up and stays warm a while.

The 1997 Ford F-250 with the 4.6L is an overhead cam aluminum block engine. It is somewhere in the middle as for how long it takes to warm up.

I had a friend who happened to live very close to his work and his car never really got time to warm up. He changed the oil and it was so milky that he thought he either had a bad head gasket or cracked head. He began doing more testing and drove the car on some decently long trips for experimentation to see what the problem was and there was no more milk in his oil. He finally came to the conclusion that all the short trips were not good for his oil or engine at all and made a point to drive a littler farther than work or the store a couple times per week. This is a Mustang with the Ford 4.6L.


#6

You’re right. It depends on the vehicle AND the weather.
AND the destination. A 30 mile drive to see a gorgeous blond with deep blue eyes is a short drive. A 30 mile commute to work is a long drive.


#7

That is like the old Albert Einstein quote about relativity. “When you are courting a nice girl an hour seems like a second. When you sit on a red-hot cinder a second seems like an hour. That’s relativity.”


#8

Yup. Einstein was right-on about that one…