Automotive Longevity. How Long Will it Last

...Just following and reading this thread. Very fascinating discussions on viscosity and longevity. My observations on longevity are that we have come along way in building better engines, higher (tighter) tolerances etc. This by itself has allowed engines to last longer. I also believe manufacturers have cheapened vehicles (Lifetime CVT's) and added complexity and "plastics" to the equation. Does anyone here find a CVT a viable long-term solution on a vehicle choice? I sure don't.

Back on topic though... IMHO... there are not a whole lot of new vehicles produced these days that will still be around 300-400k. Primarily because of lack of maintenance and IMHO... manufactures aren't 100% focused on "longevity". I think the whole point of these conversations is to maximize engine "lifespan".
 
It's been discussed in a few other threads. The premise is that the tribofilm that was built up from running the oil for awhile is somehow stripped off to some degree when an oil change is done. It has nothing to do with the engine sitting turned off and the oil draining off the parts. The tribofilm is built-up and stuck to the surface of parts, regardless of how long the oil drains off the surface.

One theory on why the Ford Coyote engine starts ticking right after an oil change is because the previous tribofilm gets stripped off parts with an oil change and the friction level between moving parts increases and triggers some kind of mechanical ticking. The ticking also instantly goes away if an oil friction modifier (like MolyLube CeraTec) is added to the oil, which pretty much points to the friction level as the ticking trigger.
Why does the new oil wipe away the previous oil's tribofilm in the first place, even if they are identical oil formulations though? Is it because the high lever of fresh dispersants?
 
My 2005 bmw 325i is now reaching 248.450 miles, while that may look like an akward number in miles it translates to 400.000km's which is above average high in europe and most normal people think a car will not make it this high.

This n52 engine puts out 220hp out of a 2.5l inline 6. This means it puts out 88hp per liter. For example a 2005 lamborghini murcialago produces 580hp out of a 6.2l v12 making it 93.5hp per liter. A 2005 dodge viper makes 60 hp per liter and a corvette c6 makes 71.

Considering this i would say that because of this it can be considered as a pretty ''high'' performance motor meaning that a lot of horsepower is squezed out of a pretty small normaly aspirated high revving engine.

Hauling a 1600kg stationwagon around, towing boats and trailers and driving 110mph/180kmh for hours and hours on cruisecontrol on the highway makes me think this engine has seen a pretty ''hard'' life. It also sees 7000rpm regulary.

It has seen 5w30 ll04 oil all its life and has always had its oci at 18k miles/ 30k kms.0

Motor is fully original as is timing chain etc..

I think the trick to achieve this comes from multiple factors:

- Well built/designed engine with appropriate tolerances and decent timing chain. It cosumes a quart per 2200 miles by design, they all do this.
If there is an inherent flaw in engine design you can use the best oil you want but the problems will come sooner or later.
- Using high quality oils, it has seen Castrol, Total, Shell and Fuchs throughout its life.
- Maintaining the OCI's according to how the vehicles is used. It mostly sees 100+ mph highway runs 50 miles a day. This gets the oil up to temp nicely and thus ''cleanses'' it from moist / fuel etc.. I think most people underestimate that they only make short trips and a lot of people also do this very ''slowly'' never letting their engine work out/get it up to temp causing sludge and dilluted oil etc..


A lot of people advised me to go to a thicker oil but i am not a believer in that thicker oil offers more protection. My idea is that as long as a good film is maintained this is sufficient. A lot of modern race and rally cars are running superthin oils.

I think in average an engine is designed to make it up to 200k miles with 20k ocis and only short distance trips. Then it should be fully worn, full of sludge and discarded like the rest of the vehicle. This is how economics work, only us bitogers think we will take our cars into the grave.😜

I think in the past 20 years its also clearly visable cars are designed to not last as long anymore, but this is compensated because the manufacturing and tooling processes are so good these days.
20 years ago it was much harder to make cars as good as they are now. So this basicly evens it out.
You drive the car at 100 + mph for over 50 miles each day? 😳

Or did you mean 100 + kilometers per hour?
 
^^^ His words where:

"It mostly sees 100+ mph highway runs 50 miles a day."
 
I am only looking at engines that have no particular problems in design....The hypothesis is that cooler running high RPM engines last longer than hotter running engines, despite using thinner oils.

There is no question that the choice of ultra thin, very high quality oil is a winning "secret" in motorsports. As you note, maintaining oil temps in the ideal range (for the viscosity) provides adequate protection in many cases. We can, for example, run a well designed, turbocharged, high boost, 600HP 4cylinder road race engine on 0W-20 oils if we actively manage oil temps to about 180F. This ain't easy by the way :) and requires a well designed dry sump system with active control and large heat exchangers.

However, the use of UOA results to determine engine wear is in error. Despite claims to the contrary, the only way to determine component wear rates is physical inspection with precise equipment and methodology. Or, run to failure...

Furthermore, wear rates do decrease as temps increase. (to a point about 300F), especially cylinder and rings. So the thought of "cold operation" to accommodate an uber thin oil may or many not be compatible depending on desired outcome.

Add in the fact that higher HTHS is correlated with lower cylinder and ring wear.

Without active modification of oil systems and engine management, followed by side by side testing and disassembly, I suspect we will never know whether you are preventing engine problems by using an ultra low viscosity oil in an ultra high performance engine. The up side is that it is difficult to tax these engines in normal street driving.
 
When I worked for Mobil Oil, we had large quantities of drained, low time, turbine oil. Some Esso/BP/Eastman 2380 and a large quantity of Mobil 254 (HTS high thermal stability). Because the oil was clean and Danny was poor, and the drain oil was free, he used it in his 2.8L V6 Chevy Camaro and changed it frequently.

This oil is ester based, low viscosity (5 cSt) and does not contain typical automotive additives. Danny drove like a typical kid, extracting every ounce of HP that engine could produce. Yes, it clattered like crazy, especially on startup, as this was just a pushrod Chevy engine. To the best of my knowledge, the engine never failed. Was this better than the typical oils of the day? Who knows...

I think you are running much the same experiment.
 
However, the use of UOA results to determine engine wear is in error. Despite claims to the contrary, the only way to determine component wear rates is physical inspection with precise equipment and methodology. Or, run to failure...
Like the experts who do controlled scientific engine wear studies, like the Southwest Research Institute does.
 
...Just following and reading this thread. Very fascinating discussions on viscosity and longevity. My observations on longevity are that we have come along way in building better engines, higher (tighter) tolerances etc. This by itself has allowed engines to last longer. I also believe manufacturers have cheapened vehicles (Lifetime CVT's) and added complexity and "plastics" to the equation. Does anyone here find a CVT a viable long-term solution on a vehicle choice? I sure don't.

Back on topic though... IMHO... there are not a whole lot of new vehicles produced these days that will still be around 300-400k. Primarily because of lack of maintenance and IMHO... manufactures aren't 100% focused on "longevity". I think the whole point of these conversations is to maximize engine "lifespan".
IMO the sliver of customer who think a passenger car/truck should last 300k-400k miles with minimal maintenance is miniscule. They don't even pop up on the radar of automakers because these customers by in large don't buy new, or newly used. They are 3rd, 4th owners.
 
Of course, 100MPH in a 200MPH car is not taxing the engine. By percentage of peak HP, it's probably on the order of 20%.
Yeah i think about 30-40% load at 3000 3500 rpm. Unfortunatly its not a 200mph car😬 Fastest i could manage was 140mph.

This bmw was offcourse designed to last on the german autobahns so its made for long high speed trips, my previous car a french peugeot 206 1.6 16v city car was not designed for highspeed trips. Even though the engine never failed and also made it to 210k miles on 20k intvervals it would run very hot on long highspeed trips.

It had an oil temp gauge and after about 15 minutes it would go up to 140 150 degrees celcius, the water temp always was fine.

That same engine is now still used in a trackday car, the guy that bought it from me teared it down to check all the specs and said it was still within all factory tolerances and looked fine so there was no work needed to be done to it.
 
The key to longevity is to avoid the beginning of wear for as long as possible.

Once wear sets in, components get loose, start "banging around" and wear only accelerates at a rapid pace.
 
My 2005 bmw 325i is now reaching 248.450 miles, while that may look like an akward number in miles it translates to 400.000km's which is above average high in europe and most normal people think a car will not make it this high.

This n52 engine puts out 220hp out of a 2.5l inline 6. This means it puts out 88hp per liter. For example a 2005 lamborghini murcialago produces 580hp out of a 6.2l v12 making it 93.5hp per liter. A 2005 dodge viper makes 60 hp per liter and a corvette c6 makes 71.

Considering this i would say that because of this it can be considered as a pretty ''high'' performance motor meaning that a lot of horsepower is squezed out of a pretty small normaly aspirated high revving engine.

Hauling a 1600kg stationwagon around, towing boats and trailers and driving 110mph/180kmh for hours and hours on cruisecontrol on the highway makes me think this engine has seen a pretty ''hard'' life. It also sees 7000rpm regulary.

It has seen 5w30 ll04 oil all its life and has always had its oci at 18k miles/ 30k kms.0

Motor is fully original as is timing chain etc..

I think the trick to achieve this comes from multiple factors:

- Well built/designed engine with appropriate tolerances and decent timing chain. It cosumes a quart per 2200 miles by design, they all do this.
If there is an inherent flaw in engine design you can use the best oil you want but the problems will come sooner or later.
- Using high quality oils, it has seen Castrol, Total, Shell and Fuchs throughout its life.
- Maintaining the OCI's according to how the vehicles is used. It mostly sees 100+ mph highway runs 50 miles a day. This gets the oil up to temp nicely and thus ''cleanses'' it from moist / fuel etc.. I think most people underestimate that they only make short trips and a lot of people also do this very ''slowly'' never letting their engine work out/get it up to temp causing sludge and dilluted oil etc..


A lot of people advised me to go to a thicker oil but i am not a believer in that thicker oil offers more protection. My idea is that as long as a good film is maintained this is sufficient. A lot of modern race and rally cars are running superthin oils.

I think in average an engine is designed to make it up to 200k miles with 20k ocis and only short distance trips. Then it should be fully worn, full of sludge and discarded like the rest of the vehicle. This is how economics work, only us bitogers think we will take our cars into the grave.😜

I think in the past 20 years its also clearly visable cars are designed to not last as long anymore, but this is compensated because the manufacturing and tooling processes are so good these days.
20 years ago it was much harder to make cars as good as they are now. So this basicly evens it out.

Between euro spec 30 weight and 40 weight there isn't a huge difference in viscosity. Most BMW manuals allow you to use either one

However, lots of people don't run 10W60 in M cars because they find it too thick for daily usage. So there is plenty of evidence that in high performance cars the oil is spec'ed for track usage.

Not too many people go down to 20 weight like Dr. Haas though. This is very bold
 
...Just following and reading this thread. Very fascinating discussions on viscosity and longevity. My observations on longevity are that we have come along way in building better engines, higher (tighter) tolerances etc. This by itself has allowed engines to last longer. I also believe manufacturers have cheapened vehicles (Lifetime CVT's) and added complexity and "plastics" to the equation. Does anyone here find a CVT a viable long-term solution on a vehicle choice? I sure don't.

Back on topic though... IMHO... there are not a whole lot of new vehicles produced these days that will still be around 300-400k. Primarily because of lack of maintenance and IMHO... manufactures aren't 100% focused on "longevity". I think the whole point of these conversations is to maximize engine "lifespan".

Lifetime CVTs? Fluid change requirements seem pretty common.
 
My 2005 bmw 325i is now reaching 248.450 miles...

This n52 engine puts out 220hp out of a 2.5l inline 6. This means it puts out 88hp per liter. For example a 2005 lamborghini murcialago produces 580hp out of a 6.2l v12 making it 93.5hp per liter. A 2005 dodge viper makes 60 hp per liter and a corvette c6 makes 71.

It cosumes a quart per 2200 miles by design, they all do this.
I enjoyed reading your perspective. As a former BMW 325i owner I can relate to it. A few comments:

I recall the N52 engine was rated at 201 hp here in the US so I looked it up and in EU the engine did in fact develop more hp. From my research it was 215 hp. So 86 hp per liter which is still respectable but there are many NA engines from the era that were higher. I don't think it's fair to compare the N52 with large displacement OHV engines, they're different beasts. My 2003 & 2004 Toyota/Yamaha 2ZZ-GE 1.8L makes 180hp (100 hp/liter). Some versions of the Honda K20 VTEC were rated even higher, 210+ hp from 2 liters.

I owned a 2001 BMW 325i which I believe had the M54 engine, rated at 181hp. I really wanted to like that car but it was a maintenance nightmare. Eventually I threw in the towel and sold it. No other car gave me so many problems and headaches. The most frustrating thing was that the same parts kept failing over and over. BMW must have known this but didn't bother revising the part design and were happy to keep making profits selling the same old new poorly engineered parts. I am surprised your car still runs with so many miles. Even if the engine is still original, I wonder how many thermostats, window regulators and VANOS solenoids, etc failed to date.

The large oil capacity (6.5L?) helps but it is impressive the engine only consumes 1L/2200 miles after a lifetime of extended OCI. That said, my 325i didn't consume nearly as much so I don't think it's "normal". It only had 82k when I sold it, though. Another thing to note is, neither of my two high revving 100hp/l Toyota engines consumes any oil, at least not enough to even register on the dipstick after 6K miles.

Is your car made in Germany? Mine was assembled in South Africa, perhaps that had something to do with the sub-par reliability.
 
I enjoyed reading your perspective. As a former BMW 325i owner I can relate to it. A few comments:

I recall the N52 engine was rated at 201 hp here in the US so I looked it up and in EU the engine did in fact develop more hp. From my research it was 215 hp. So 86 hp per liter which is still respectable but there are many NA engines from the era that were higher. I don't think it's fair to compare the N52 with large displacement OHV engines, they're different beasts. My 2003 & 2004 Toyota/Yamaha 2ZZ-GE 1.8L makes 180hp (100 hp/liter). Some versions of the Honda K20 VTEC were rated even higher, 210+ hp from 2 liters.

I owned a 2001 BMW 325i which I believe had the M54 engine, rated at 181hp. I really wanted to like that car but it was a maintenance nightmare. Eventually I threw in the towel and sold it. No other car gave me so many problems and headaches. The most frustrating thing was that the same parts kept failing over and over. BMW must have known this but didn't bother revising the part design and were happy to keep making profits selling the same old new poorly engineered parts. I am surprised your car still runs with so many miles. Even if the engine is still original, I wonder how many thermostats, window regulators and VANOS solenoids, etc failed to date.

The large oil capacity (6.5L?) helps but it is impressive the engine only consumes 1L/2200 miles after a lifetime of extended OCI. That said, my 325i didn't consume nearly as much so I don't think it's "normal". It only had 82k when I sold it, though. Another thing to note is, neither of my two high revving 100hp/l Toyota engines consumes any oil, at least not enough to even register on the dipstick after 6K miles.

Is your car made in Germany? Mine was assembled in South Africa, perhaps that had something to do with the sub-par reliability.

Some of the problems are rectified on the aftermarket parts. The OEM Wahler thermostat always leaks from temp sensor. The aftermarket Behr one does not. I think its a similar story with the window regulators - there are some better aftermarket ones
 
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