facundo_olanoCode is run more than read (2023)
And cars are driven more than worked on, but putting the oil filter inaccessibly in the middle of the engine block is still an unforgiveable sin.
What if there's an efficiency in engine design by placing the filter in the middle that leads to a +2mpg improvement for the driver? Or that it fails, on average, 22k miles later into it's life? Not all hard-to-repair-yourself designs are malicious...
If it is a part with a regular maintenance schedule, it should be designed for maintainability.
Most maintainability conflicts come from packaging and design for assembly.
Efficiency more often comes into conflict with durability, and sometimes safety.
Right but what I'm getting at is that there can be tradeoffs that might make designing for maintainability mean optimizing for something less important to the end user.
Do you optimize an engine for how easy it is to replace a filter once or twice a year (most likely done by someone the average car-owner is already paying to change their oil for them), or do you optimize it for getting better gas mileage over every single mile the car is driven?
We're talking about a hypothetical car and neither of us (I assume) design engines like this, I'm just trying to illustrate a point about tradeoffs existing. To your own point of efficiency being a trade with durability, that's not in a vacuum. If a part is in a different location with a different loading environment, it can be more/less durable (material changes leading to efficiency differences), more/less likely to break (maybe you service the hard-to-service part half as often when it's in a harder to service spot), etc.
Only TCO matters, that is the efficiency you actually optimize for, ie dollar per mile[1]not miles per gallon.
If the car is going to need to be in shop for days needing you to have a replacement rental because the model is difficult to service and the cost of service itself is not cheap , that can easily outweigh any marginal mpg gain .
Similarly because it is expensive and time consuming you may likely skip service schedules , the engine will then have a reduced life, or seizes up on the road and you need an expensive tow and rebuild etc .
You are implicitly assuming none of these will change if the maintenance is more difficult , that is not the case though
This is what OP is implying when he says a part with regular maintenance schedule to be easily accessible.
[1] of which fuel is only one part , substantial yes but not the only one
I'm just gonna copy and paste a response to another similar comment:
The point that I am making (obviously, I think) is that tradeoffs exist, even if you don't think the right decision was made, your full view into the trade space is likely incomplete, or prioritizes something different than the engineers.
Putting some random number of hypothetical mpg improvement was clearly a mistake, but I assumed people here would be able to get the point I was trying to make, instead of getting riled up about the relationship (or lack thereof) of oil filters and fuel efficiency.
I’m no mechanical engineer, but I would assume those extreme tradeoffs occur more often when repairability is not prioritized from early iterations. I.e. “boss we’re 90% into the design cycle why are you bringing up the position of the oil filter now?”
There’s definitely a programming equivalent as well…
If the engine failed due to missing oil change because of the difficulty, the whole car is gone. The waste in cost, material, and environmental impact far outweighs the savings in 2mpg improvement.
Glad to know in this hypothetical car scenario the owner decided to not get an oil change leading to the total loss of the vehicle. That seems very realistic and definitely something that car designs should be optimized around.
Or, we consider that 2mpg across 100,000 cars can save 3,500,000 gallons of gas being burned for the average American driving ~12k miles per year. And maybe things aren't so black and white. You're argument, in this hypothetical, is that negligent car owner who destroys their car because they're choosing to not change the oil is worth burning an extra 3.5millon gallons of gasoline.
To be fair, you are constructing an entirely hypothetical car scenario where oil filter placement leads to a 5-10% increase in fuel efficiency.
We're already in the land of the fucking ridiculous. Let's have fun with it.
I'm using this hypothetical to illustrate the point that: tradeoffs exist, and that you (we) may not have full insight into the full complexity of the trade space that the engineers were working with.
Putting some random number of hypothetical mpg improvement was clearly a mistake, but I assumed people here would be able to get the point I was trying to make, instead of getting riled up about the relationship (or lack thereof) of oil filters and fuel efficiency.