Highway vs. City Driving OCIs

[camrydriver111]

A lot of people here seem to shorten their OCIs and explain that it's because they do city driving. Should I shorten my OCIs because of city driving?

A lot of manufacturers do recommend shorter OCIs in "extreme conditions". However is city driving by itself considered an extreme condition?

How would you adjust your OCI if you drove:

100% highway
50% highway / 50% city
100% city

 

[Brybo86]

According to my guesstimations based on my Hondas Maintenance minder....

I can go about 10k miles to 0% MM during the summer with lots of long highway trips.
In the winter it will hit 0% by like 7500miles while doing a lot of short trips.

I think the biggest factor in MM system is cold starts. Imo they cause the MM to decrease faster than anything else.

I bet a taxi used for 12 hrs a day in the dead of winter would have a long MM OCI, similar to my car when used for long highway trips.

 

[jimbrewer]

I think it's really a short trip vs. Long trip thing. There's nothing extreme about my commute except it's only 3+ miles long. Also, of course the average speed is less, so the hours of operation are more.

 

[Quattro Pete]

I would base it on the amount of fuel consumed. You are burning more fuel in city driving. You are also burning more fuel when short tripping, because the engine is running below operating temp.

What is your car's recommended OCI in ideal (non-extreme) conditions? What is your average MPG at 100% hwy? What is your average MPG at 100% city? Answer these, and I'll tell you what your city OCI should be.

 

[HKPolice]

Hondas should be changed at 5% OLM at the latest, not 0%. Honda's own PDF says this: http://www.sporthonda.com/Dealersites/7154/images/pdf/mms.pdf

Honda's own Technical doc about the OLM system says that there is upto 15% error rate as well.

http://hondakarma.com/attachments/engine-oil-deterioration-monitoring-system-pdf.12590/
Section 5.2:
Quote:
The Maximum degree of error measured as the calculated value for the oil life compared to the actual level of deterioration was 15%.


So realistically, if you change at 0% with a 15% error rate, you could be 20% overdue. I personally change the minute it hits 15% because oil is so cheap anyways.

 

[sicko]

Originally Posted By: camrydriver111
A lot of people here seem to shorten their OCIs and explain that it's because they do city driving. Should I shorten my OCIs because of city driving?

A lot of manufacturers do recommend shorter OCIs in "extreme conditions". However is city driving by itself considered an extreme condition?

How would you adjust your OCI if you drove:

100% highway
50% highway / 50% city
100% city



I put 16k-18k miles a year on my car, and currently I do an oil change every 6 months. I'm going to do a UOA with my next oil change to make sure everything is okay. But based on the scenarios you broke out, here's what I'd do assuming my mileage stayed about the same:

100% highway: Oil change every 6 months
50% highway / 50% city: Oil change every 6 months
100% city: Oil change every 4 months, or every 6 months if a UOA showed the oil could easily handle it.


As for your OCI and if it should be adjusted b/c of your city driving, that depends on a lot of actors. What's your current OCI? What vehicle do you drive. What oil do you use, and is it conventional or synthetic? How many miles are you putting on it? What's your driving style? etc. We'd need to know more information before we could suggest what you should do to your OCI.

 

[raytseng]

I think you've missed some fine details in your links.

For your first link. The 5% is from sportshonda-a dealer who wants you to come in, not from honda. Perhaps they're looking out for you and don't want panicked people who are at 0% and saying i need to come in RIGHT NOW!!!.
The real owner's manual says you can take it to 0%.


For your 2nd link, they wrote about the error, I think they are aware of it and took it into account.


They say later on "The calculated oil life data was set with consideration with the above error rates."
Then in the conclusion
"The accuracy of this system has been verified and the calculations were conducted to avoid the calculation error from the actual oil deterioration."

I think you need to give these engineers more credit that they aren't complete idiots and they'll assume the 15% error as the worst case. So it's not that you could go 15% negative.

They'd set it so when you're at 0% worst case you could be at 0% but you really could have up to 15% left and most likely you are at 7.5% left (assuming 15% covers both +/- sides).

 

[HKPolice]

Originally Posted By: raytseng
I think you've missed some fine details in your links.

For your first link. The 5% is from sportshonda-a dealer who wants you to come in, not from honda. Perhaps they're looking out for you and don't want panicked people who are at 0% and saying i need to come in RIGHT NOW!!!.
The real owner's manual says you can take it to 0%.


For your 2nd link, they wrote about the error, I think they are aware of it and took it into account.


They say later on "The calculated oil life data was set with consideration with the above error rates."
Then in the conclusion
"The accuracy of this system has been verified and the calculations were conducted to avoid the calculation error from the actual oil deterioration."

I think you need to give these engineers more credit that they aren't complete idiots and they'll assume the 15% error as the worst case. So it's not that you could go 15% negative.

They'd set it so when you're at 0% worst case you could be at 0% but you really could have up to 15% left and most likely you are at 7.5% left (assuming 15% covers both +/- sides).



Wrong. Owner's manual makes ZERO mention that it's "OK" to go to 0%. It only says that the minder will pop up at 15% and will read "SERVICE OIL LIFE" at 5%. http://techinfo.honda.com/rjanisis/pubs/OM/NV0707/NV0707G00016A.pdf

Fact remains that there is up to 15% error. It never specified how they "compensated" for this. It could be that the 5% SERVICE OIL LIFE point is the only compensation built into the system. So when at 5%, it could be +7.5% for 12.5% or -7.5% for -2.5% overall or worse. Honda is in the business of selling cars, they don't care if the engine sludges up after 10yrs, they only care about the warranty period.

 

[HTSS_TR]

Originally Posted By: HKPolice
Honda is in the business of selling cars, they don't care if the engine sludge up after 10 yrs, they only care about the warranty period.

Honda and all other manufactures do care about their car's reliability and the reputation that Honda earned over the last 30-40 years with their engines is hard to dispute.

Honda and Toyota engines are known to be reliable, therefore they don't have to give dealers large kickback to sell their cars, that can be as much as $500-600 or more a car, multiply that with 1,000,000(or more per year) cars now you see good number.

 

[raytseng]

Do whatever you want. If you don't trust honda, you're never going to trust them anyway.

When your gas light goes on, that doesn't mean you suddenly have 0 gas in your car and your car stops.

But anywhere here's a manual for the 2015 accord where they say on p488:
For 5%:
The engine oil has almost reached
the end of its service life, and the
maintenance items should be
inspected and serviced as soon as
possible.

Notice it says "almost", not your car is going to die now.

Then for 0% it says: The engine oil life has passed.

It paraphrases exactly what I said. It doesn't make sense to present 5% which is supposed to be be interpreted as meaning 0%. If they wanted to give that message they'd just display 0% instead (when it's 5%).

You can check other manuals too for other honda products, they all break it down to 15%, 5%,and 0+miles, but the tables might be slightly different.

http://owners.honda.com/vehicles/warranty?year=2015&model=Accord-Sedan

http://techinfo.honda.com/rjanisis/pubs/OM/AH/A2A154DOM/enu/A2A154DOM.pdf


But anyway oil is not a step function. If you're getting very uptight that your oil suddenly turning bad on a specific number, your oil is already marginal when it was getting down low anyway. It's not cinderella at the ball.

 

[Kuato]

Originally Posted By: camrydriver111
A lot of people here seem to shorten their OCIs and explain that it's because they do city driving. Should I shorten my OCIs because of city driving?

A lot of manufacturers do recommend shorter OCIs in "extreme conditions". However is city driving by itself considered an extreme condition?

How would you adjust your OCI if you drove:

100% highway
50% highway / 50% city
100% city


Verified with UOAs using Amsoil on our '04 Wrangler:

99% highway: more than 12000 miles, the longest interval tested. The TBN was still in the 3.xx range.

95% city: around 7k, same oil.

 

[dino33]

According to Redline Oil:

Q: How often should I change my Red Line oil?
It depends on how you drive. If you do a lot of city driving or low speed/low frequency driving, we recommend oil changes at 7500 miles. Vehicles that see more highway driving can go a maximum of 15,000 to 18,000 miles with an oil filter change in between. Modern filter technology and the latest, clean-burning fuels have reduced the solids that contaminate oil, so frequent filter changes aren't usually necessary


http://www.redlineoil.com/techinfo_faq.aspx

 

[KitaCam]

Different engines (even of the same model) use oil differently under different driving...some more on the highway, some more around town....

The concern is as suggested when taking SHORT runs, turning off the engine before it gets to operating temperature....

If a car is driven for just 5 minutes often, that would fall under the definition of "severe"....regardless of how long/short the OCI for such cars, they should be taken out on the highway once a week for 15 minute runs to burn off condensation and any collected deposits.

 

[HKPolice]

Originally Posted By: raytseng
Do whatever you want. If you don't trust honda, you're never going to trust them anyway.

When your gas light goes on, that doesn't mean you suddenly have 0 gas in your car and your car stops.

But anywhere here's a manual for the 2015 accord where they say on p488:
For 5%:
The engine oil has almost reached
the end of its service life, and the
maintenance items should be
inspected and serviced as soon as
possible.

Notice it says "almost", not your car is going to die now.

Then for 0% it says: The engine oil life has passed.

It paraphrases exactly what I said. It doesn't make sense to present 5% which is supposed to be be interpreted as meaning 0%. If they wanted to give that message they'd just display 0% instead (when it's 5%).

You can check other manuals too for other honda products, they all break it down to 15%, 5%,and 0+miles, but the tables might be slightly different.

http://owners.honda.com/vehicles/warranty?year=2015&model=Accord-Sedan

http://techinfo.honda.com/rjanisis/pubs/OM/AH/A2A154DOM/enu/A2A154DOM.pdf


But anyway oil is not a step function. If you're getting very uptight that your oil suddenly turning bad on a specific number, your oil is already marginal when it was getting down low anyway. It's not cinderella at the ball.


No of course it doesn't turn bad instantly, but multiply this by 20 oil changes and this is how varnish/sludge build up happens. What's the point of extending an OCI by only 5% when oil is so cheap. I don't get you people.

No I don't trust Honda or any car brand. They're companies who want to make a profit, not your friend. You people don't realize how many recalls & technical disasters all the major manufacturers have had to deal with over the years.

Honda alone: Civic R18 engine block cracking from 06-09, extended warranties for all vehicles.

4spd automatic transmission failures especially in the odyssey, class action lawsuit resulting in compensation for all people who had to pay out of their pockets for repairs.

V6 engine excessive oil consumption in 08-13 models, class action lawsuit resulting in extended warranty for 8 years.

Takata airbag recall: Honda didn't report 1729 incidents, and was FINED $70 MILLION for lying.

This is just a partial list for Honda, google everything and see for yourself. All of these incidents happened to people who were just 'following the manual' like you. Every other car manufacturer out there has a similarly long list. And you still want to trust Honda's OLM even though they ADMITTED upto 15% error rate in the calculation?

GM even had a recall because their OLM was letting the car run way too long between oil changes. The result? Worn out balance chains. Over 770k cars affected.
http://autoweek.com/article/car-news/gm-reprogram-some-oil-life-monitors

Do whatever you want, I'm just glad I'll never be buying a used car from you.

 

[HKPolice]

Originally Posted By: HTSS_TR
Originally Posted By: HKPolice
Honda is in the business of selling cars, they don't care if the engine sludge up after 10 yrs, they only care about the warranty period.

Honda and all other manufactures do care about their car's reliability and the reputation that Honda earned over the last 30-40 years with their engines is hard to dispute.

Honda and Toyota engines are known to be reliable, therefore they don't have to give dealers large kickback to sell their cars, that can be as much as $500-600 or more a car, multiply that with 1,000,000(or more per year) cars now you see good number.



Honda: Civic R18 engine block cracking from 06-09, extended warranties for all vehicles.

V6 engine excessive oil consumption in 08-13 models, class action lawsuit resulting in extended warranty for 8 years.

Toyota: 2.4L 2AZ-FE engine 06-11: excessive oil consumption, extended warranties for all cars involved. Class action lawsuit pending.

1MZ-FE 3.0L V6 engine: the sludge monster, no extended warranties.

1ZZ-FE 1.8L engine 98-03: excessive oil consumption, cracks develop in the ECU for 05-08 models leading to a recall, over 1million cars affected.

This is just a partial list of engine related issues, I could go on and on about smaller things and lets not forget the biggest recall of all: unintended acceleration. Reputation means nothing.

 

[Pontual]

Appart from the warming up phase, I think it Depends if you hit too much jammed traffics or not. If you're running most miles at last gear at 50mph, city driving wouldn't get much shorter OCIs.

 

[linksep]

Guys... stop... The OP doesn't drive a Honda according to his username so all the Honda talk is moot.

To the OP: You left our important details like your current city/hwy mix, preferred oil (conventional, blend, synthetic...), car (I assume Camry, but maybe you're talking about your kid's Subaru WRX) and your average city/hwy trip length...

Scenario 1) 100% city, engine running about 5 minutes at a time. I might stick with the old 3K miles OCI.

Scenario 2) 100% city, you're a Cab driver and the engine never runs less than 4 hours at a time... 10-15K OCI.

Scenario 3) 50/50 split City/Hwy, but all trips are 10 min or less, also probably stick with 3K miles OCI.

Scenario 4) 50/50 split, 6 days per week you drive 10 min or less "city" twice per day, on the 7th day you drive 60+ minutes highway twice (to grandmother's house and back). 7.5-10K OCI depending on oil/filter used.

Scenario 5) 100% highway, you live right on the highway and work/shop/play within 5 minutes engine running time...3K OCI.

Scenario 6) 100% highway, you live in Vermont and work in Maine... driving straight through New Hampshire twice per day without stopping (60 minutes or more at highway speed every time you start the car). 10-15K mile OCI...

That assumes mid range name-brand oil, mid-range filter, and you want between 100K and 300k miles from their vehicle.

If you're trying to join the million mile club or leasing (renting) the car, or you only buy oil/filters the the dollar store, that will change OCI...

 

[lars11]

My cars speak of "severe duty service intervals" and that includes:
Frequent trips shorter than 10 miles (low sustained engine temps)
Winter driving at under -10C (low sustained engine temps)
Dusty conditions (filter life and wear)
Uphill driving or towing (high loads)
Start/stop driving (City, few miles per gallon, brakes etc)

Sometimes the service intervals has to do with other factors than oil, like checking for worn brakes, clutches, tires, linkages, transmission fluids, but often enough that coincides with the need for OCIs.

But driving only 3 mi city one way, day in and out, will make your oil suffer from low temps and probably quite few miles per gallon. So in that case, I wouldn't go over a year and maybe 6-8000 miles max.

 

[OneEyeJack]

In the real world the OLM's will improve the life of an engine because they will remind drivers to get an oil change and many of them will take the time to do it. Most drivers know nothing about maintenance except that it's a pain and costs money, wastes time and it's difficult to tell if it's making a difference or not. The oil goes somewhere under the hood but only after the old oil is somehow removed. Synthetic oil is better because the guy changing the oil told you so and the proof is that it costs more than conventional oil. There's other stuff under the hood as well but if the car still starts it must all be okay. If you miss an oil change it's not a big deal like forgetting to get the car washed and vacuumed out. People will know when it's time to purchase a new car because they know how many payments are left on their current ride. Just accept the fact that you'll be making car payments the rest of your life and don't worry about the maintenance. If something unexpected happens you'll just pay the bill or trade up sooner than otherwise planned just like you do with the dishwasher. After all, it's just a car and if it's more interesting than your dishwasher then so much the better because you usually spend more time with the car than that dishwasher. As long as the buttons on both the car and dishwasher work than you're "good=to-go".

 

[camrydriver111]

Thank you for the replies.

Originally Posted By: linksep
To the OP: You left our important details like your current city/hwy mix, preferred oil (conventional, blend, synthetic...), car (I assume Camry, but maybe you're talking about your kid's Subaru WRX) and your average city/hwy trip length...


I was looking for general rules of thumb to follow that could be applied to most cars. Like half of normal OCI is a pretty common recommendation.