Since semi-retiring and starting my own business from home it means I'm driving a lot less now. Great.
I record the mileage on the car every year or so and have calculated that I'm currently averaging less than 2k miles/year. 162.5m/month to be precies.
I'm actually relishing driving less as I consider it an absolute 'quality of life' benefit and I feel sorry for anyone who gets stuck in traffic jams on a daily commute. No way I'd ever go back to that bullshit!
In any case, it got me considering what my oil change interval should be now.
I used to do intermediate changes at 7500 miles where the manual for the zed calls for 15k miles with the theory that it would prolong the life of the engine exponentially. I used to do that with a previous BMW (with the M52TUB25 engine) and got 270k miles out of it until it was t-boned and written off. snif. So I'm convinced intermediate oil changes are nothing but beneficial.
The car's a 21 year old BMW Z4 (E85 / M54B30 engine) with 154100 miles on the clock.
I use a PELA oil pump to suck out the oil through the dipstick. It's the best way of extricating every last drop and before today I've pulled out 7L where the engine is specced for 6.5L with the max level showing on the dipstick.
Now, there are a multitude of theories as to how often the OCI should be when you're doing low mileages. The concensus is usually 1 year regardless of low mileage on motoring forums. Some say 2 years is fine. I'm coming up to 2 years since the last change and the oil still looks and smells fine with just less than 2k miles driven. Honey-coloured with no burnt smells etc. I shifted to 10W/40 from 5W/40 a couple of changes back. Driving style is mostly relaxed with a couple of 'spirited' bursts but nothing that goes near the redline in any gear and about 70-80% motorway (freeway). Trips never shorter than 1/2hour to ensure any condensation is evaporated off etc.
One of the first things I changed out when I first bought it was the crispy old PCV system as it was on the original and was very crispy. A new throttlebody was swapped in as the original failed in the first 500 miles of my ownership.
While I was fiddling around that area I cleaned and flushed the ICV, swapped in a new intake hose, checked the DISA, replaced the thermostat and water-pump and swapped in a new valve cover gasket.
The engine purrs like a kitten, even from cold, in the cold and idles evenly with no hunting or other weirdness. Still pulls like a train even though i think the VANOS solenoid s could benefit from a refresh.
I make sure to 'exercise' it and take it out for at least a half-hour spin every week or 2 weeks at the most if I don't have any need to drive anywhere in the meantime.
With all the above said, I'm toying with the idea of going with a 3yr OCI if I stick to my current annual mileage.
I don't subscribe to the notion that oil will turn into acid over time. You need to have the actual combustion process occurring for that to take place, so I think it's a nonsense to suggest in this context.
Thoughts?
From 2016. Looking clean enough. No mayo or gunk.
A new alternator had been installed previous to my ownership which is one less failure-anxiety, for now.
Sparkers a bit grimy but all consistently-so. Threw some new ones in of course.
All buttoned up ready to go. Haven't had to go back in there for anything major for about 8 years now. Fingers x'd.
I record the mileage on the car every year or so and have calculated that I'm currently averaging less than 2k miles/year. 162.5m/month to be precies.
I'm actually relishing driving less as I consider it an absolute 'quality of life' benefit and I feel sorry for anyone who gets stuck in traffic jams on a daily commute. No way I'd ever go back to that bullshit!
In any case, it got me considering what my oil change interval should be now.
I used to do intermediate changes at 7500 miles where the manual for the zed calls for 15k miles with the theory that it would prolong the life of the engine exponentially. I used to do that with a previous BMW (with the M52TUB25 engine) and got 270k miles out of it until it was t-boned and written off. snif. So I'm convinced intermediate oil changes are nothing but beneficial.
The car's a 21 year old BMW Z4 (E85 / M54B30 engine) with 154100 miles on the clock.
I use a PELA oil pump to suck out the oil through the dipstick. It's the best way of extricating every last drop and before today I've pulled out 7L where the engine is specced for 6.5L with the max level showing on the dipstick.
Now, there are a multitude of theories as to how often the OCI should be when you're doing low mileages. The concensus is usually 1 year regardless of low mileage on motoring forums. Some say 2 years is fine. I'm coming up to 2 years since the last change and the oil still looks and smells fine with just less than 2k miles driven. Honey-coloured with no burnt smells etc. I shifted to 10W/40 from 5W/40 a couple of changes back. Driving style is mostly relaxed with a couple of 'spirited' bursts but nothing that goes near the redline in any gear and about 70-80% motorway (freeway). Trips never shorter than 1/2hour to ensure any condensation is evaporated off etc.
One of the first things I changed out when I first bought it was the crispy old PCV system as it was on the original and was very crispy. A new throttlebody was swapped in as the original failed in the first 500 miles of my ownership.
While I was fiddling around that area I cleaned and flushed the ICV, swapped in a new intake hose, checked the DISA, replaced the thermostat and water-pump and swapped in a new valve cover gasket.
The engine purrs like a kitten, even from cold, in the cold and idles evenly with no hunting or other weirdness. Still pulls like a train even though i think the VANOS solenoid s could benefit from a refresh.
I make sure to 'exercise' it and take it out for at least a half-hour spin every week or 2 weeks at the most if I don't have any need to drive anywhere in the meantime.
With all the above said, I'm toying with the idea of going with a 3yr OCI if I stick to my current annual mileage.
I don't subscribe to the notion that oil will turn into acid over time. You need to have the actual combustion process occurring for that to take place, so I think it's a nonsense to suggest in this context.
Thoughts?
From 2016. Looking clean enough. No mayo or gunk.
A new alternator had been installed previous to my ownership which is one less failure-anxiety, for now.
Sparkers a bit grimy but all consistently-so. Threw some new ones in of course.
All buttoned up ready to go. Haven't had to go back in there for anything major for about 8 years now. Fingers x'd.
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