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Discussion Starter · #1 ·
Maintenance interval, "severe driving conditions" and "extremely cold weather"

The maintenance schedule calls driving in "extremely cold weather" an example of "severe driving conditions" and halves the oil change interval to 3,000 miles. Is there a specific example of what driving in extremely cold weather means?

I had a Honda Accord years ago that had similar guidance for cars in Canada. I live in Minnesota, which isn't Canada, but as the dealer was fond of pointing out we actually live north of the majority of the Canadian population. It's part "buy more service" sales pitch, but there's a certain logic to it.

I'm guessing the oil change part of cold weather as a severe driving condition is oriented towards the vehicle seeing cold starts from being parked outside, not an engine warmed up and just running in cold ambient air. I heat my garage to 42 F, so roughly half my winter engine starts are always above freezing, and the other half have a sitting time in sub-freezing temperatures of less than 8 hours (probably closer to 4).

I'm probably overthinking this, but I've never been totally at ease with contemporary cars and their long oil duty cycles. Any time I see the manufacturer suggesting shorter oil change cycles like this it makes me wonder if longer duty cycles aren't part sales pitch for "less maintenance cost", not a reflection of superior engineering and miracle petrochemistry.
 

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The maintenance schedule calls driving in "extremely cold weather" an example of "severe driving conditions" and halves the oil change interval to 3,000 miles. Is there a specific example of what driving in extremely cold weather means?

I had a Honda Accord years ago that had similar guidance for cars in Canada. I live in Minnesota, which isn't Canada, but as the dealer was fond of pointing out we actually live north of the majority of the Canadian population. It's part "buy more service" sales pitch, but there's a certain logic to it.

I'm guessing the oil change part of cold weather as a severe driving condition is oriented towards the vehicle seeing cold starts from being parked outside, not an engine warmed up and just running in cold ambient air. I heat my garage to 42 F, so roughly half my winter engine starts are always above freezing, and the other half have a sitting time in sub-freezing temperatures of less than 8 hours (probably closer to 4).

I'm probably overthinking this, but I've never been totally at ease with contemporary cars and their long oil duty cycles. Any time I see the manufacturer suggesting shorter oil change cycles like this it makes me wonder if longer duty cycles aren't part sales pitch for "less maintenance cost", not a reflection of superior engineering and miracle petrochemistry.
You nailed on the term but your thoughts are miles away. First of all, the modern cars (using synthetic oil) is designed to be operated in habitable area. Now, that's too broad of an explanation because it really depends on how it's operated: the various duty cycle of the engine load w/ respect to time. In other words, how hard you work the engine vs the time you let it rest.

The duty cycle I'm talking about is not about oil per-se, it's the operational duration vs load. Let's get into the math for a bit: if you graph it, X-operational duration and Y-load (or RPM), to represent the different style of driver in the habitable area, we can qualify two distinctive styles of "severe driving".

1. pizza man delivery w/ intermittent stops: graph will look like short narrow waves
2. hauling/towing 5000lbs in long trip: graph will look like tall wide waves

Both scenarios put a lot of stress on the engine and tranny. Between those two scenarios, it's normal. Very small percentage of the group falls toward the ends of that spectrum, most (if not all) will service their Ascent at every 6000miles. Whether you believe that or not, the manual allow you to make your own interpretation. Hopefully, a concept that I proposed make some sense.

If you propose your case, a general plan of what you're use your vehicle for so we can help (e.g. drive it daily, store it, driving style, etc...). Otherwise, the thread might turn into some half written PhD thesis paper.
 

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Winter my use and temps falls into that slightly above average abuse so most winter changes I change oil around 5000 miles. Summers I typically have one change that falls into to the 4000 mile range due to extreme heat, towing and long highway hours.

Its kinda your call on how tough your usage is. Towing regularly and stuck in crawling traffic several days a week gets into that really tough zone with lower OCI mileage in most regions.
 

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Discussion Starter · #4 ·
To me, at least, if a lot of your driving falls into the usual longstanding ideas about what's hard on an engine (lots of stop and go, lots of towing, etc), then you'd want the severe duty oil change cycle. My own specific driving habits are about 25% urban streets, 25% urban freeways (which can vary from stop and go, slow and go, to all go) and 50% suburban freeways (continuous highway speeds). No towing, generally light passenger/cargo loads.

I would think my own driving mix is extremely ordinary, maybe even on the lighter end of the spectrum because of a relatively high amount of constant speed "highway miles", and I would have to think that I'm generally in the center of whatever average driving conditions engineering based the maintenance schedule on.

But I'm curious about the "extreme cold" part and how to interpret that. Mostly I see it based on cold engine starts, where the car has been sitting > 4 hours in sub-freezing weather. It's also possible to interpret this is "a lot of snow" and some extra engine effort associate with poor traction situations.

Generally, though, I'm inclined towards 3000 mile oil change intervals because it's a pretty safe bet. Nobody put extra engine wear on their car because they changed their oil too often. Although there is some kind of complex thinking that might suggest that sticking to 6K puts $1500 in your pocket towards buying the next car sooner or something.
 

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To me, at least, if a lot of your driving falls into the usual longstanding ideas about what's hard on an engine (lots of stop and go, lots of towing, etc), then you'd want the severe duty oil change cycle. My own specific driving habits are about 25% urban streets, 25% urban freeways (which can vary from stop and go, slow and go, to all go) and 50% suburban freeways (continuous highway speeds). No towing, generally light passenger/cargo loads.

I would think my own driving mix is extremely ordinary, maybe even on the lighter end of the spectrum because of a relatively high amount of constant speed "highway miles", and I would have to think that I'm generally in the center of whatever average driving conditions engineering based the maintenance schedule on.

But I'm curious about the "extreme cold" part and how to interpret that. Mostly I see it based on cold engine starts, where the car has been sitting > 4 hours in sub-freezing weather. It's also possible to interpret this is "a lot of snow" and some extra engine effort associate with poor traction situations.

Generally, though, I'm inclined towards 3000 mile oil change intervals because it's a pretty safe bet. Nobody put extra engine wear on their car because they changed their oil too often. Although there is some kind of complex thinking that might suggest that sticking to 6K puts $1500 in your pocket towards buying the next car sooner or something.

3000mile oci is just wasteful with modern oils and cars. Wasted money, time and oil. Unless your a yard mow and blow guy dragging a trailer every day all week.
 

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To me, at least, if a lot of your driving falls into the usual longstanding ideas about what's hard on an engine (lots of stop and go, lots of towing, etc), then you'd want the severe duty oil change cycle. My own specific driving habits are about 25% urban streets, 25% urban freeways (which can vary from stop and go, slow and go, to all go) and 50% suburban freeways (continuous highway speeds). No towing, generally light passenger/cargo loads.

I would think my own driving mix is extremely ordinary, maybe even on the lighter end of the spectrum because of a relatively high amount of constant speed "highway miles", and I would have to think that I'm generally in the center of whatever average driving conditions engineering based the maintenance schedule on.

But I'm curious about the "extreme cold" part and how to interpret that. Mostly I see it based on cold engine starts, where the car has been sitting > 4 hours in sub-freezing weather. It's also possible to interpret this is "a lot of snow" and some extra engine effort associate with poor traction situations.

Generally, though, I'm inclined towards 3000 mile oil change intervals because it's a pretty safe bet. Nobody put extra engine wear on their car because they changed their oil too often. Although there is some kind of complex thinking that might suggest that sticking to 6K puts $1500 in your pocket towards buying the next car sooner or something.
The burden is on you to quantify the "extreme cold". I've traveled thru the Rockies during the winters in the last decade and my minimal experience have shown that starting cars in sub-zero degrees overnight isn't a problem (assuming that cars have been properly maintained).

It's only critical if you can't get the engine/tranny up to temperature for optimal lubrication. Both the engine and tranny are water cooled. The cooling system is designed to precisely control the lubrication temp. That means that there's no legitimate reason to change oil less than 6000mi if you use it for daily driving to work.

The group of concern for low temp (or high heat) operation is the air cooled porsche guys where there engine/oil temp is sorta uncontrollable.
 

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There is a reason some car and motorcycle forums have a place for never ending oil threads.

Short trips will build some more contamination in your oil. It is designed to carry that until you change it. But normal driving is ok. Your modern, synthetic oil is not going to wear out in 6000 miles. Extreme cold could involve more idling time, that isn’t as efficient. The engine warms slightly slower when is very cold, so You could make that argument But I would say heat is a greater factor for wear and cold can be the opposite. That’s why Minnesotans live longer?. Or does it just feel that way...

I have lived in Minnesota cold my whole life. I most recently put well over 200,000 miles on a couple of KIAs, changing the oil myself at 10,000 mile intervals. Both vehicles still weren’t using a quart of oil between those 10k changes. Was I prematurely wearing out the engines? Doubt it. modern engines run clean and modern oils are good. Unless you are short tripping, long towing or racing, relax. It’s all good. The 6k recommendation, in my opinion, is conservative. And I’m sticking with it through the warranty period.
 
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