Petrol/Gas B58 Overheat at Highway (Motorway) Speed

[Eric]

Observe the same for the (displayed...) water temp.
What does your engine oil temp do when towing heavily (long steep inclines) in hot weather conditions? Mine quickly exceeds 130°C if I don't cut back.
I strongly doubt this was the case when the vehicle was new, but cannot prove it.
I asked for other's experience on several occasions here, but obviously there's no similar experience...

Ah, to be honest I don't think I've had the engine temperature screen on when heavy towing on an incline ( the reason being when towing a big load of horse hay the wife is usually with me and plays about with the audio screen annoying me with her taste in music [ word used loosely)but will see next time I tow. When I have had the temperature screen on the engine has never been above 101°C

 

[TD5-90]

Ah, to be honest I don't think I've had the engine temperature screen on when heavy towing on an incline ( the reason being when towing a big load of horse hay the wife is usually with me and plays about with the audio screen annoying me with her taste in music [ word used loosely)

but will see next time I tow. When I have had the temperature screen on the engine has never been above 101°C

Ok, thanks! Maybe winter time on the northern hemisphere isn't the right time to carry out temperature testing...

 

[MrMike]

Observe the same for the (displayed...) water temp.
What does your engine oil temp do when towing heavily (long steep inclines) in hot weather conditions? Mine quickly exceeds 130°C if I don't cut back.
I strongly doubt this was the case when the vehicle was new, but cannot prove it.
I asked for other's experience on several occasions here, but obviously there's no similar experience...

What viscosity oil are you using? 0-w30 at 130deg is at its limit in regard to lubrication from what I have read, there are a few instances in Australia where this viscosity has caused engine damage.

 

[NQ94]

What viscosity oil are you using? 0-w30 at 130deg is at its limit in regard to lubrication from what I have read, there are a few instances in Australia where this viscosity has caused engine damage.

The HTHS high temperature high shear is a 150C test for modern oils. The life of the oil would be reduced and classed as servere duty working at near those temperatures. The 0W 30 oil viscosity has not caused the engine damage its likely the oil has not been changed at earlier intervals because of servere duty cycles and the engine oil has run to full service distance with excessive oxidisation.

 

[MrMike]

The HTHS high temperature high shear is a 150C test for modern oils. The life of the oil would be reduced and classed as servere duty working at near those temperatures. The 0W 30 oil viscosity has not caused the engine damage its likely the oil has not been changed at earlier intervals because of servere duty cycles and the engine oil has run to full service distance with excessive oxidisation.

So you're suggesting (as I do) more frequent oil changes if towing to reduce the oil from degrading?
This is an issue for those in that situation as most adhere to the manufacturers recommended internals

 

[NQ94]

So you're suggesting (as I do) more frequent oil changes if towing to reduce the oil from degrading?
This is an issue for those in that situation as most adhere to the manufacturers recommended internals

Absolutely change oil at shorter intervals with high amounts of heavy towing. Heavy towing especially at high ambient temperatures has higher fuel use and is classed as severe duty operation. Same should be done with the transmission if towing a lot. The oil has to work harder because of higher continuous cylinder pressures and temperatures for longer times (duty cycle). Engine oil isn't just a lubricant it's a coolant and a waste control fluid.
In heavy duty applications it's becoming more common to base engine oil changes on total fuel burnt to determine service intervals.

 

[MrMike]

Absolutely change oil at shorter intervals with high amounts of heavy towing. Heavy towing especially at high ambient temperatures has higher fuel use and is classed as severe duty operation. Same should be done with the transmission if towing a lot. The oil has to work harder because of higher continuous cylinder pressures and temperatures for longer times (duty cycle). Engine oil isn't just a lubricant it's a coolant and a waste control fluid.
In heavy duty applications it's becoming more common to base engine oil changes on total fuel burnt to determine service intervals.

I changed my oil from 0-W30 to 5-W30, assuming this would help?

 

[AWo]

To be honest....that is not a good idea.

As far as I know the oil specification 0W is the highest value and 20 as the lowest (0W 20 and 0W 30). As a rule you should not increase the first number over its highest value and not decrease the second number lower than its lowest value.

Why?

Because you leave the designated operation specifications. Let me explain why.

First you need to know that the first and second number of the oil viscosity have different meanings. The first number expresses how good a cold oil can be pumped. The highest viscosity here (which is 0W) is the limit of what the system can handle to have the oil reaching all lubrication points fast enough and how good it can flow away from there to provide cooling while it is cold.
It is clear, that in a cold state the oil is still thick enough to cope with any pressure applied to it, as it still can cope with it as it is getting hotter. That's why the first number only addresses the ability of being pumped.

--> If you exceed the oil viscosity here, the oil will be too thick to be pumped as it needs. That's why you should never exceed the maximum allowed value of the first number you find in the specs. so if the specs read 0W30 and 5W30 you can change to a 5W oil at maximum.

The second number represents the ability to take pressure. It is clear that a hot oil is less thick than when it is cold, it can be pumped fast enough. The ability to be pumped is thereby not an issue with hot oil and therefore the first value doesn't play such a role in this state. But you should never go lower that what is allowed by the second value because that would mean the oil can not take the pressure applied to it as its viscosity is too less than what the specification allows. That leads to wear of moving parts. Using the example above you shout never use an oil which is lower than 30.

--> If you get a lower hot oil viscosity than in the specification you create wear in the engine due to the oils inability to take load/pressure while it is hot.

The Grenadiers B58 spec says 0W20 or 0W30, which is pretty narrow but can be explained by the striving for reducing the least internal friction. That is achieved by oil with low viscosity, as it can be pumped easier. As the lowest number is 0W in both cases you should never go to 5W or even higher.

My article regarding this issue: https://matsch--und--piste-de.trans..._sl=de&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wapp

My advice.
AWo

 

[MrMike]

To be honest....that is not a good idea.

As far as I know the oil specification is 0W as the highest value and 20 as the lowest (0W 20 and 0W 30). As a rule you should not increase the first number over its highest value and not decrease the second number lower than its lowest value.

Why?

Because you leave the designated operation specifications. Let me explain why.

First you need to know that the first and second number of the oil viscosity have different meanings. The first number expresses how good a cold oil can be pumped. The highest viscosity here (which is 0W) is the limit of what the system can handle to have the oil reaching all lubrication points fast enough and how good it can flow away from there to provide cooling while it is cold.
It is clear, that in a cold state the oil is still thick enough to cope with any pressure applied to it, as it still can cope with it as it is getting hotter. That's why the first number only addresses the ability of being pumped.

--> If you exceed the oil viscosity here, the oil will be too thick to be pumped as it needs. That's why you should never exceed the maximum allowed value of the first number you find in the specs. so if the specs read 0W30 and 5W30 you can change to a 5W oil at maximum.

The second number represents the ability to take pressure. It is clear that a hot oil is less thick that when it is cold, it can be pumped fast enough. The ability to be pumped is thereby not an issue with hot oil and the second value of the oil specification. you should never go lower that what is allowed because that would mean the oil can not take the pressure applied to it leading to wear of moving parts. using the example above you shout never use an oil which is lower than 30.

--> If you get a lower hot oil viscosity than in the specification you create wear in the engine due to the oils inability to take load/pressure.

The Grenadiers B58 spec says 0W20 or 0W30, which is pretty narrow but can be explained by the striving for reducing the least internal friction. That is achieved by oil with low viscosity, as it can be pumped easier. As the lowest number is 0W in both cases you should never go to 5W or even higher.

My article regarding this issue: https://matsch--und--piste-de.trans..._sl=de&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wapp

My advice.
AWo

Interesting, my local dealer used 5/30 at the first oil change.

 

[AWo]

Just because he is a dealer doesn't mean that he knows about these facts. Even if he should....read the full article linked there and make you own thoughts. Physical facts don't care about opinions, but everybody is free in who to believe....

If I'm wrong and 5W is within the specifications, you can use it of course, but my general statement remains true.

AWo

 

[TD5-90]

What viscosity oil are you using? 0-w30 at 130deg is at its limit in regard to lubrication from what I have read, there are a few instances in Australia where this viscosity has caused engine damage.

Still the recommended 0W30 with the appropriate BMW spec.
I do intermediate oil changes between the service intervalls, but haven't noticed a difference between old & new oil.

 

[NQ94]

To be honest....that is not a good idea.

As far as I know the oil specification 0W is the highest value and 20 as the lowest (0W 20 and 0W 30). As a rule you should not increase the first number over its highest value and not decrease the second number lower than its lowest value.

Why?

Because you leave the designated operation specifications. Let me explain why.

First you need to know that the first and second number of the oil viscosity have different meanings. The first number expresses how good a cold oil can be pumped. The highest viscosity here (which is 0W) is the limit of what the system can handle to have the oil reaching all lubrication points fast enough and how good it can flow away from there to provide cooling while it is cold.
It is clear, that in a cold state the oil is still thick enough to cope with any pressure applied to it, as it still can cope with it as it is getting hotter. That's why the first number only addresses the ability of being pumped.

--> If you exceed the oil viscosity here, the oil will be too thick to be pumped as it needs. That's why you should never exceed the maximum allowed value of the first number you find in the specs. so if the specs read 0W30 and 5W30 you can change to a 5W oil at maximum.

The second number represents the ability to take pressure. It is clear that a hot oil is less thick than when it is cold, it can be pumped fast enough. The ability to be pumped is thereby not an issue with hot oil and therefore the first value doesn't play such a role in this state. But you should never go lower that what is allowed by the second value because that would mean the oil can not take the pressure applied to it as its viscosity is too less than what the specification allows. That leads to wear of moving parts. Using the example above you shout never use an oil which is lower than 30.

--> If you get a lower hot oil viscosity than in the specification you create wear in the engine due to the oils inability to take load/pressure while it is hot.

The Grenadiers B58 spec says 0W20 or 0W30, which is pretty narrow but can be explained by the striving for reducing the least internal friction. That is achieved by oil with low viscosity, as it can be pumped easier. As the lowest number is 0W in both cases you should never go to 5W or even higher.

My article regarding this issue: https://matsch--und--piste-de.trans..._sl=de&_x_tr_tl=en&_x_tr_hl=de&_x_tr_pto=wapp

My advice.
AWo

5W30 falls within the 0W 30 viscosity ranges. The difference is the base oil is higher a viscosity to start with and there are less viscosity improvers VI to cover the viscosity range and this is the polymer additive that suffers the most shear degregation through the moving parts of an engine in a multi grade oil.
5W 30 has good cold weather starting flow at -30C something we will never see in Australia but is likely in parts of Europe. Cold weather starting temperatures need to be specified when writing about oil to avoid misinterpretation by the reader. An oil with less viscosity improvers will perform better and suffer less viscosity degradation in severe working and hot environments.

 

[Tazzieman]

So @NQ94 in the desert where it can go from 0 to plus 40C in the day, what is the oil viscosity you suggest?

 

[NQ94]

So @NQ94 in the desert where it can go from 0 to plus 40C in the day, what is the oil viscosity you suggest?

In my personal car (non BMW specific) if the spec is 0W 30. I would still use 5W 30 as it still falls with in the 0W 30 specs and the operation would be well above 0C and severe duty the majority of the time. 0W -35C, 5W -30C, 10W -25c, 15W -20C these are the minimum winter temps the oil will flow relatively easily at start up. In the past for temperatures 40C and above a 40 grade oil was recommended.
Today the ACEA HTHS oil spec at 150C has become one of the most important specs for Euro and Japanese light duty engine oils with most passenger vehicle oils specified for both petrol and diesel engines with the introduction
of direct petrol injection.
The interesting thing with oil specification and rarely ever mentioned is to look at the specification on an old engine platform, like B58 & B57, when the engine was originally released and then see how most manufacturers have decreased the viscosity specifications on that platform as the emission rules have changed over the years.

 

[Clark Kent]

In my personal car (non BMW specific) if the spec is 0W 30. I would still use 5W 30 as it still falls with in the 0W 30 specs and the operation would be well above 0C and severe duty the majority of the time. 0W -35C, 5W -30C, 10W -25c, 15W -20C these are the minimum winter temps the oil will flow relatively easily at start up. In the past for temperatures 40C and above a 40 grade oil was recommended.
Today the ACEA HTHS oil spec at 150C has become one of the most important specs for Euro and Japanese light duty engine oils with most passenger vehicle oils specified for both petrol and diesel engines with the introduction
of direct petrol injection.
The interesting thing with oil specification and rarely ever mentioned is to look at the specification on an old engine platform, like B58 & B57, when the engine was originally released and then see how most manufacturers have decreased the viscosity specifications on that platform as the emission rules have changed over the years.

I saw an interesting observation on a B58 YT channel recently. He pulled down a couple of different generations of oil pump to confirm what is plastic and what is metal. There is a significant chunk of plastic in the B58 oil pump that forms part of the pressure chamber. That part has a history of cracking if the oil viscosity is too high. We're mostly talking about guys who track their cars and run thick oils.
Oil condition and viscosity has been implicated in VANOS failures over the years.
My point being there are less obviously places in the B58 where chunky oil could cause issues. Changing from 0W to 5W won't bother the oil pump. Going north of 40wt might.

View: https://youtu.be/e160WA7Q7Mo?si=Y_epCjY-HHxj7rNy

 

[NQ94]

I saw an interesting observation on a B58 YT channel recently. He pulled down a couple of different generations of oil pump to confirm what is plastic and what is metal. There is a significant chunk of plastic in the B58 oil pump that forms part of the pressure chamber. That part has a history of cracking if the oil viscosity is too high. We're mostly talking about guys who track their cars and run thick oils.
Oil condition and viscosity has been implicated in VANOS failures over the years.
My point being there are less obviously places in the B58 where chunky oil could cause issues. Changing from 0W to 5W won't bother the oil pump. Going north of 40wt might.

View: https://youtu.be/e160WA7Q7Mo?si=Y_epCjY-HHxj7rNy

Above 40wt oil is pretty heavy for most engines these days and can cause issues with hydraulic lash adjusters, chain tensioners and cam phasers when cold. People also forget that oil can increase in viscosity due to contamination and oxidisation if left too long between changes. Being motor racing related the issues the video explains can also be attribute to sustained high oil temps affecting internal plastic parts over time not just the higher viscosity oil causing the failures.
Hopefully Grenadier didn't inherit the plastic oil pump. It just seems like a cheap out for forced obsolescence and poor design, up there with wet belts.

 

[Clark Kent]

Above 40wt oil is pretty heavy for most engines these days and can cause issues with hydraulic lash adjusters, chain tensioners and cam phasers when cold. People also forget that oil can increase in viscosity due to contamination and oxidisation if left too long between changes. Being motor racing related the issues the video explains can also be attribute to sustained high oil temps affecting internal plastic parts over time not just the higher viscosity oil causing the failures.
Hopefully Grenadier didn't inherit the plastic oil pump. It just seems like a cheap out for forced obsolescence and poor design, up there with wet belts.

I think Grenadier will have inherited whatever the current series oil pump was. I'm not aware of longevity issues with the design. Just that it doesn't like being mechanically stressed by our of spec thick oil that takes a bit more work to squeeze through the chamber. The Grenadier B58 oil spec is 0W-20. That's warfarin thin.