General Oil check

[AWo]

Many last century Porsche engines that require relatively thick oils with high film strength have been destroyed by "modern" mechanics and DIYers who assume thin synthetics are better than the oils Porsche specified at the time.

The problem is not that these oils are synthetic. It's their viscosity.

There are two reasons why we will see more and more thin oils with low viscosity (the viscosity is directly linked to the capability to face pressure from surfaces).

For the sake of reducing CO2 output of ICE's the engineers need to reduce internal friction resistance. Oil is part of the resistance. Higher viscosity means more friction. By using low viscosity oils, like 0W-10, friction is reduced. Low viscosity oils in combination with low performance oil pumps become more and more difficult to keep oil pressure up. The BMW engines in the IG use an electronically controlled oil pump. I have no experience with this, I don't know if that is good or bad in the end....but I know that the vane pump type in our Ford Puma engine is totally crap. I still prefer the classic gear pump. Check the aftermarket....there are more and more powerful aftermarket oil pumps availabe for a quite large range of engines which faced weak lubrication based damages.

The second reason for more thinner oils is that the manufacturing got more precise and very small and equal gaps are possible. On one hand, that gives more power, as you have less blow by gases, on the other hand, you must increase the throughput of oil, to get the heat away from the surfaces at the small gaps.

Welcome to the future.

However, for old engines or engines which run quite a lot of kilometers I would change to the oil in the specs with the highest viscosity. My Td5 engine with 465.000 km got 5W-30 for a long time. I changed to 5W-40 for some time now. That will compensate for a certain amount of wear. The upper value is the important one, you should stay with what the OEM allows. The upper value reduces over time as it is based on additives. The lower value represents the viscosity of the base oil used. As additives disappear over time and use the upper value get's lower and the oil becomes thinner, thereby it looses its capabilty to face pressure. Contamination with other fluids and solids may work against getting thinner, but the dilution has other drawbacks. And still, the capability to face pressure gets lost more and more.

Fun Fact: The original Mini shares its oil between engine and gearbox. It used to have a high viscosity oil xW-50 if I remember correctly. that is because the shear forces in the gearbox made it aging very fast loosing its viscosity quickly. The oil change intervall was about 4,000 to 5,000 km.

So be happy with modern life time oils which can be used for 60 trillion kilometers...without any drawback...

AWo

 

[DaveB]

The problem is not that these oils are synthetic. It's their viscosity.

There are two reasons why we will see more and more thin oils with low viscosity (teh viscosity is directly linked to the capability to face pressure from surfaces).

For the sake of reducing CO2 output of ICE's the engineers need to reuce internal friction resitance. Oil is part of the resitance. More viscosity means more friction. By using low viscosity oils, like 0W-10, friction is reduced. Low viscosity oils in combination with low performance oil pumps it becomes more and more difficult to keep oil pressure up. The BMW engines in the IG use an electronically controlled oil pump. I have no experience with this, I don't know if that is good or bad in the end....but I know that the vane pump type in our Ford Puma engine is totally crap. I still prefer the classic gear pump. Check the aftermarket....there are more powerful aftermarket oil pumps availabe for a quite large range of engines which faced weak lubrication based damages.

The second reason for more thinner oils is thatthe manufacturing got more precise and very small and equal gaps are possible. On one hand, that gives more power, as you have less blow by gases, on the other hand, you must increase the throughput of oil, to get the heat away from the small gaps.

Welcome to the future.

However, for old engines or engines which run quite a lot of kilometers I would change to the oil in the specs with the highest viscosity. My Td5 engine with 465.000 km got 5W-30 for a long time. I changed to 5W-40 for some time now. That will compensate for a certain amount of wear. The upper value is the important one, you should stay with what the OEM allows. The upper value reduces over time as it is based on additives. The lower value represents the viscosity of the base oil used. As additives disappear the upper value get's lower and the oil becomes thinner, thereby it loose its capabilty to face pressure. Contamination with other fluids and solids may work against dilution, but these have other drawbacks. And still, the capability to face pressure gets lost more and more.

Fun Fact: The original Mini shares its oil between engine and gearbox. It used to have a high viscosity oil xW-50 if I remember correctly. that is because the shear forces in the gearbox made it aging very fast loosing its viscosity quickly. The oil change intervall was about 4,000 to 5,000 km.

So be happy with modern life time oils which can be used for 60 trillion kilometers...without any drawback...

AWo

I seem to recall some Landrover person referring to it as dumbarse - W30
Or was it 5W- dumbarse???

 

[Clark Kent]

Project Farm did some testing on this topic.

View: https://youtube.com/watch?v=xtSwaF2evTU&feature=shared

 

[NQ94]

The problem is not that these oils are synthetic. It's their viscosity.

There are two reasons why we will see more and more thin oils with low viscosity (the viscosity is directly linked to the capability to face pressure from surfaces).

For the sake of reducing CO2 output of ICE's the engineers need to reduce internal friction resistance. Oil is part of the resistance. Higher viscosity means more friction. By using low viscosity oils, like 0W-10, friction is reduced. Low viscosity oils in combination with low performance oil pumps become more and more difficult to keep oil pressure up. The BMW engines in the IG use an electronically controlled oil pump. I have no experience with this, I don't know if that is good or bad in the end....but I know that the vane pump type in our Ford Puma engine is totally crap. I still prefer the classic gear pump. Check the aftermarket....there are more and more powerful aftermarket oil pumps availabe for a quite large range of engines which faced weak lubrication based damages.

The second reason for more thinner oils is that the manufacturing got more precise and very small and equal gaps are possible. On one hand, that gives more power, as you have less blow by gases, on the other hand, you must increase the throughput of oil, to get the heat away from the surfaces at the small gaps.

Welcome to the future.

However, for old engines or engines which run quite a lot of kilometers I would change to the oil in the specs with the highest viscosity. My Td5 engine with 465.000 km got 5W-30 for a long time. I changed to 5W-40 for some time now. That will compensate for a certain amount of wear. The upper value is the important one, you should stay with what the OEM allows. The upper value reduces over time as it is based on additives. The lower value represents the viscosity of the base oil used. As additives disappear over time and use the upper value get's lower and the oil becomes thinner, thereby it looses its capabilty to face pressure. Contamination with other fluids and solids may work against getting thinner, but the dilution has other drawbacks. And still, the capability to face pressure gets lost more and more.

Fun Fact: The original Mini shares its oil between engine and gearbox. It used to have a high viscosity oil xW-50 if I remember correctly. that is because the shear forces in the gearbox made it aging very fast loosing its viscosity quickly. The oil change intervall was about 4,000 to 5,000 km.

So be happy with modern life time oils which can be used for 60 trillion kilometers...without any drawback...

AWo

Lower viscosity oil are apparently used to save CO2 in all environments and operating conditions. However running a higher viscosity base oil in hotter environments and higher duty cycles may possibly increase some CO2 but in the long run it improves engine and oil life and reduces oil waste in harsh conditions. At various fleet sites we have proven this and worked with manufacturers with regular oil sampling and testing and have introduced longer oil change intervals in engines, transmission and drivelines with less wear and oil use for the operating conditions encountered. Car manufactures generally specify an oil suitable for all world climates and operating conditions to reduce fuel consumption, costs and dealer oil inventory.

 

[Tazzieman]

So be happy with modern life time oils which can be used for 60 trillion kilometers...without any drawback...

I've got multiple old cars from 1964-1985. They are all fed the same 20W-50 mineral oil with added zinc.
Tappets , crank bearings etc are all happy.
Easy peasy!
Modern cars are in many ways like modern kids. Needy, entitled and difficult to fix when they break down.

 

[Tinerfeño]

Please remember that too high viscosity may destroy small clearance bearings as flow will be reduced.
Zinc is only needed if engine doesn't have rollers on valve gear (like old V8 engines).

 

[NQ94]

Please remember that too high viscosity may destroy small clearance bearings as flow will be reduced.
Zinc is only needed if engine doesn't have rollers on valve gear (like old V8 engines).

More than clearances the biggest change in the last 30 years I have seen has been the quality and stability of oils, particularly synthetic oils and additive technologies. Now we see low viscosity synthetic oils with temperature and lubrication structure stability and considerably longer working life with better lubrication that was not available years ago.

 

[Tazzieman]

Zinc is only needed if engine doesn't have rollers on valve gear (like old V8 engines).

& like air cooled 911 engines

 

[hoohoohama]

Interesting enough, I also had the 'Refill 500ml' for off road come up - vehicle was level. I put in EXACTLY 500ml. I performed a measurement again and both levels said 'Ok'. I drove for about half an hour and an oil 'overfill' warning in amber colour came up on the main screen and amber triangle on the fault screen. I removed 250ml and both indicated 'Ok'. Note the engine oil dipstick was a little over the full mark after I added the 500ml. (I did say in a previous thread I would have to get used to the electronic oil measurement version... alas no, +1 for old school engine dipsticks - I've NEVER had to remove engine oil before due to an 'overfill'.)

I also had this Refill 500ml for off road (on road ok) while doing the engine oil check today, I am curious how oil level is declining over time, what is considered normal and how often we should refill.