What Engine hours do we think is good for an oil change interval?

[Ang]

Newest post I could find about this is from 2003.
I'm finding that one of my Gas vehicles is doing a lot of hours for the mileage, often only 20 or so miles per hour, meaning that I'm doing maybe 200+ hours for 4000 miles, Which is when id normally change it. I'm going to start tracking hours, but at how many hours should I change the oil if I meet it before 4000 miles?

 

[DCDG]

interesting thought I always use miles or months for an oil change interval. Normally when I hear of hours on oil I think of outdoor power equipment, diesels and farm machines.

 

[Strumpan_]

With a good oil 500 hours shouldnt be an issue. We do 1000 hours on semi synthetic 10w-30. The loaders do have a lot more oil than a car though.

 

[UGASpike]

My .02 is utilize the idle hours if your vehicle can display it. 50 hours over 100 miles driven vs 50 hours over 3000 miles driven might be hard to track for some but that oil will be two kinds of degraded.

Good thought I’m here for the thread

 

[Hohn]

Newest post I could find about this is from 2003.
I'm finding that one of my Gas vehicles is doing a lot of hours for the mileage, often only 20 or so miles per hour, meaning that I'm doing maybe 200+ hours for 4000 miles, Which is when id normally change it. I'm going to start tracking hours, but at how many hours should I change the oil if I meet it before 4000 miles?

Change by fuel burn.

200x the oil pan capacity in fuel burn. If it holds 5 quarts, then change at (5*200/4)= 250 gallons of fuel burn.

 

[Zee09]

That's hard to say without specifics
I change my gas every 7 hours.......

 

[PontiacHO]

First responder vehicles that we maintained always were scheduled for service based on the manufacturers’ rough-severe service intervals. These always have extended periods of idling. 3500 miles was an an average mileage used.

 

[kschachn]

You may find some information in these previous threads on this topic:

Thread 'Engine Hours instead of Mileage'

Jul 5, 2024

Does anyone change oil based on Engine Hours instead of mileage? Seems like it might be a good idea because it factors in idling time.

• Nyati
• Replies: 31
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

Thread 'Engine Hours per OCI'

Dec 12, 2023

I just changed the oil in my Ram 1500 5.7L eTorque after 9 months and 4,954 miles. This interval was a mix of city and highway driving, but probably 50-60% city. According to the trip computer this worked out to 186 engine hours. Oil life Monitor was in the 40-ish percent remaining.

I recognize that some farm equipment and small engines specify oil changes at 200 hour intervals. At least for my use, it appears that a 5K interval gets me pretty close to that!

• The Critic
• Replies: 16
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

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• 

U

Thread 'Operating hours versus mileage for oil changes?'

Jan 15, 2023

Is anyone using engine operating hours instead of mileage for oil changes? I would think that if you spent a lot of time in traffic your operating hours would be high versus your mileage. Therefore low miles but more stress on the oil. Any good studies or experience on this? Thanks

• UNC070
• Replies: 32
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

Thread 'OCI: Engine Hours vs. Mileage'

Jul 28, 2023

For those of us with engine hour meters on our vehicles, should you use engine hours instead of mileage for determining OCI's?

For instance, it has been 2,067 miles since my last oil change. According to my cluster, it has been 82 engine hours. If I proceed with my usual 5K OCI, it will be about 200 engine hours.

• The Critic
• Replies: 27
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

O

Thread 'Engine hours vs miles'

Nov 28, 2023

What is the equation to convert engine hours to miles. I’ve read to conflicting stats. One says multiple hours x30, one says x60? Which is correct???

• otis24
• Replies: 25
• Forum: Automotive General Topics

M

Thread 'Changing oil based on engine hours'

Jul 13, 2003

Does anyone use engine hours as a schedule for oil changes? I remember an interview where the "expert" said using a 150 hour cycle for changes was a good way to simplify maintenance.

Well my car's trip computer is almost always at 150 hours when I get to 5000 miles. ( my interval)
This last time it included a fast drive to Chicago so 5000 miles came up almost 30 hours sooner. My brother has a long highway commute every day, he can put 5000 miles on his car in two months, his car sees almost no city driving.
I'm thinking of putting an hour meter on his car for him, to see if this gives a...

• mirou
• Replies: 13
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

T

Thread 'OCI based on engine hours not miles'

Mar 15, 2015

Almsot all of my wreckers and service trucks have engine hour meters yet I still maintain my fleet based on miles. Anyone doing service based on engine hours? My trucks almost never make it on the highway and are strictly in town and being used 24/7 literally. Lots of idling, tons of dust and stop and go. My drivers are hard in equipment...pedal to the metal at every stop light. For years I have contemplated rewriting my service intervals based on hours rather than miles.

Anyone doing this??? Any advice???

• ToadU
• Replies: 10
• Forum: Mechanical/Maintenance Forum

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Thread 'OCI in terms of hours vs. mileage'

Jun 15, 2006

Everyone-

Just a simple question-my truck's got an engine-hour meter on it to measure running time, and I figure that changing the oil based on hours of use might be better than mileage since it takes into account idle time.

Any idea how long the "average" OCI is in terms of engine running hours? My owners' manual doesn't specify-

thanks-

Fitz

• Fitz
• Replies: 29
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

 

[Number_35]

I wish my ScanGauge displayed engine hours.

 

[trd1zz]

Aren't hours already sort of pseudo-covered by the time interval that most MFR's specify?

You know, the whole 6 months or 5k miles, whichever occurs first (many people ignore this part as if it doesn't matter)

 

[jetman]

@Ang
A SouthWest Research Institute (SWRI) lube analysis tech came up with the following formula for OCI:
sump capacity in quarts, times 200, divided by 4, equals gallons, times the vehicles mpg = OCI in miles.
Do a search here at BITOG using SWRI.
Based on my extensive UOA reports collected on each of my vehicles, this formula gives me a good baseline for each.

 

[Samurai1225]

My trip meter will display engine run hours so I use and consider mileage & engine run time for my OCIs.

 

[Kestas]

@Ang
A SouthWest Research Institute (SWRI) lube analysis tech came up with the following formula for OCI:
sump capacity in quarts, times 200, divided by 4, equals gallons, times the vehicles mpg = OCI in miles.
Do a search here at BITOG using SWRI.
Based on my extensive UOA reports collected on each of my vehicles, this formula gives me a good baseline for each.

Is this for regular or synthetic oil?

 

[CKN]

IF you have a vehicle with an OLM the algorithms take in to account idle hours.

 

[UGASpike]

IF you have a vehicle with an OLM the algorithms take in to account idle hours.

Here is a decent video from LSJr speaking on OLM.

 

[OVERKILL]

IF you have a vehicle with an OLM the algorithms take in to account idle hours.

*iOLM, I only mention this because Toyota's OLM is not intelligent, it's just a mileage counter.

 

[OVERKILL]

My wife's truck (naturally aspired, port injected, 7 quart sump) seems to bing off the OLM at somewhere around 400-500 hours, but since we are using HPL, we've run 600-700 hours.

 

[UGASpike]

My wife's truck (naturally aspired, port injected, 7 quart sump) seems to bing off the OLM at somewhere around 400-500 hours, but since we are using HPL, we've run 600-700 hours.

I just crossed 100ish hours in my truck - 67%OLM, 3400 miles. I have a 7.5qt sump in my truck. My projected service will be near 9-10K.

Based on (7.5x200/4)= 375x20 = mile 7500 OCI.

 

[OVERKILL]

I just crossed 100ish hours in my truck - 67%OLM, 3400 miles. I have a 7.5qt sump in my truck. My projected service will be near 9-10K.

Based on (7.5x200/4)= 375x20 = mile 7500 OCI.

What's the basis for that formula?

 

[UGASpike]

What's the basis for that formula?

Hohn's formula in Post #5

Change by fuel burn.

200x the oil pan capacity in fuel burn. If it holds 5 quarts, then change at (5*200/4)= 250 gallons of fuel burn.

Multiply the total gallons of fuel burned by your MPG, and you will get the recommended OCI.