How does idling engine effect oil change intervals/wear?
 

This is not a BRZ, but my daily driver I idle 5-8 hours a week in park. It has a 2.5 NA engine and right now I am changing the oil with 0w20 synthetic every 4 months (4-5,000 miles).


Do you think this is sufficient? Any other maintenance items I should consider?

the best way to check is to have the oil analyzed.

i always forget to get the sample kits myself (matter of fact, i'm going to order a couple now), but some friends have used blackstone a few times. every response they've shown me from them is quite thorough.

https://blackstone-labs.com/

wrong blackstonelabs.

https://www.blackstone-labs.com/test...dard-analysis/

As long as it has enough oil any oil will be fine.

Unless you are a heathen Royal Purple shill then you have major issues.
Us Mobile 1 people will wipe the earth clean of "you" people.


But seriously you are overthinking this oil and idle bs.

I think the OP is concerned that he is adding wear to his oil without adding time or mileage, which are the two most common metrics that most people use to determine their oil change interval. Other metrics to consider would be whether the vehicle saw highway, town or track miles, or whether the climate was warm, cool, dusty or whatever.

If wear or degradation of oil was proportional to rpm then idling at 650-800rpms for 5-8 hours a week would be equivalent to driving for 1.5 hours at highway speed, which is an extra 100 miles a week. After four months, that is an extra 1700 miles, meaning the car will have its oil changed at 4-5k miles, but there will be 5.7-6.7k miles of wear on the oil.

I don’t think this is a big deal, especially if synthetics are used.

Every 6 months or 5k km, whichever comes first.

Opinions may vary

It seems that you missed my response above.

In a more extreme case of the OP's situation, I worked EMS ten years ago, and we would sometimes idle the ambulance for 12 hours a day, so we could run the AC during those 105 degree days Sacramento gets. Some days, we barely drove the ambulance; we would drive to post then park then wait for a call then drive back to the station. Free money--I know. We would consume a lot of diesel, so I know the equivalent miles would be a lot. Thus, if wear is proportional to rpm then idling adds wear without adding miles. In theory, this would mean that we would need to change the oil in the ambulance more often.

I would think this has to depend on the car...specifically oil capacity, since that determines how much fuel dilution the oil can take. I would imagine European cars with 10+ quart sumps wouldn't have much of a problem with your oil change interval, but maybe a 4 quart sump would.

I change mine regularly due to a few reasons

Dusty conditions, humid conditions, these conditions contaminate the oil

I also thrash the guts out of my car, my car also sits in traffic jams where my oil sits at 115° c for extended periods, and it also runs a turbo, this breaks down the oil.

I personally don't worry about oil tests, oil is cheap, and a oil change takes me about 10 minutes

Hence, as per the manual for the time, 6 months, and as per the voices in my head and old habits for distance traveled, 5k km.

Extreme, maybe, but then I enjoy servicing my car.

As for the OP, if his oil is getting hot enough to cook off moisture formed during the combustion process I would say that even at 12 month oil change intervals it should be fine.

Unless there is other factors, burnishing or glazing, alot of contamination from a rich idle washing down the bore and contaminating the oil.

Stuff like that, we have alot of diesel engined vehicles and plant where I work and it is a maintenance issue, we have vehicles idling in position for weeks on end not really moving, those engines don't really last to long.

Engines need load to clean the oil of the bores, without load the glazing and burnishing takes hold and will fuck your shit up.

I got off topic abit with the glazing and burnishing, extended periods of idling has greater issues than just the condition of your oil.

But try telling a guy in a metal box to kill the engine/aircon in 50°c heat, he will either politely tell you to sod off, or, if he does shut it down, there would be lots of paperwork after he died and then melted inside.

I reckon that is just fine.

I suggest you not overthink this situation.

:)


humfrz

I would change it more frequently just for peace of mind. Since the engine ends up running hotter idling than when driving. Remember to check your coolant level and color as well and add/flush as necessary.

But for the OP, I think his interval should be fine.

Idling is designed into the engine specs. It is expected and accounted for when they set the oil change periods. Changing it more often is not required and just throws more used oil into the environment. Synthetic oils last a long long time no matter what you are doing to them so I would not be even slightly worried about longer idle times.

Unless you're towing while idling. The slight increase in fulcrum angle at the hitch-point could shift oil to a different part of the oil pan, causing only the most anal of people to think something is wrong. :popcorn:

But this doesn't just apply to the towing situation you've described. What about idling and the permutations of degree of inclination ( +ve or -ve) plus degree of side-slope?

If you want to make this testing complete you will have to log data when the car is idling up-side-down.