5w-30 for new Honda 3.5L v6

[kschachn]

So you think that 3 or 4 working cylinders produce same amount of heat as 6 do?

It doesn’t have to in terms of operating temperature. In order for the engine to operate at the set point of the thermostat then all you need is enough heat minus radiative and convection losses.

No manufacturer would ever want an engine to operate at less than the design temperature as that would be detrimental to efficiency (as well as other problems such as excessive oil deposits).

 

[OVERKILL]

My understanding is that the heat gradient within the block changes with VCM.

I could see that, the one bank would run hotter than the other, since unlike MDS/AFM, it doesn't selectively disable cylinders in both banks, but rather an entire bank. The coolant would stay the same temperature and the total amount of heat generated would be similar, but it would be concentrated in the bank doing the work.

 

[dwcars]

You are all forgetting the fact that the only time ambient temperature affects an engine is at "cold start". At cold start the motor oil is the same temperature as the outside air. Thinner oil (0W-X0 or 5W-X0) flows more easily thru the very tight tolerance of modern engines at start up, and that is when the greater percentage of wear occurs.
Once the engine comes up to temperature, The engine's cooling system keeps the engine and its oil at temperatures that are higher than the outside temperature. So even if your outside temperature is 120 degrees, your engine cooling system will be well above that, so you do not need a heavier (XW-30 or XW-40) motor oil.

 

[dwcars]

For those that asked, I'm fine with M1 EP in 5w-30 (not 0w-20 in a V6 in hot weather)--I really don't know how to read spec sheets so I just wanted to confirm what was a good 5w-30 that will not leave valve deposits. I should also add that my morning commute is only 5 miles each way, so I don't want to go to a 40 weight. I live in SoCal, but I also drive up to the mountains in the winter where it can get quite cold, so I'd prefer to stick to a 5w rather than a 10w. I was thinking this might be good: Castrol Edge Euro 5W-30 A3/B4

At full operating temperature when driving, the 5W is completely insignificant. 5W indicates the flow rate at low temperature.

 

[OVERKILL]

You are all forgetting the fact that the only time ambient temperature affects an engine is at "cold start". At cold start the motor oil is the same temperature as the outside air. Thinner oil (0W-X0 or 5W-X0) flows more easily thru the very tight tolerance of modern engines at start up, and that is when the greater percentage of wear occurs.
Once the engine comes up to temperature, The engine's cooling system keeps the engine and its oil at temperatures that are higher than the outside temperature. So even if your outside temperature is 120 degrees, your engine cooling system will be well above that, so you do not need a heavier (XW-30 or XW-40) motor oil.

You are starting with a flawed premise. *clearances* on modern engines, with the exception of the ones designed for 0W-8 and 0W-12, are the same as they've been for the last 50+ years.

I don't believe anybody was forgetting that detail about ambient, it just isn't overly germane to a discussion about a claim that VCM reduces engine temperatures.

 

[kschachn]

You are starting with a flawed premise. *clearances* on modern engines, with the exception of the ones designed for 0W-8 and 0W-12, are the same as they've been for the last 50+ years.

I don't believe anybody was forgetting that detail about ambient, it just isn't overly germane to a discussion about a claim that VCM reduces engine temperatures.

Tolerances... oil having to flow through small ones...

Whatever next for that poor oil?

 

[Drew7a]

I get a kick out of this where people are arguing about a delta of approx 8 cst between a 20 grade and a 40 grade, but that same twenty grade had a delta of approximately 35cst between 100 degrees F and operating temp.

Yet the 40 grade will not go through the tight clearances yet a 20 when cold will

 

[dwcars]

I don't want to be 'snarky' or be a wise guy, but motor oil is a lubricant, not a "cushion". If an engine is exceptionally loose or has excessive clearances, heavier/thicker oil may slow down the consumption a bit. Current or recently built engines have very tight clearances and don't need a cushion, they need lubrication. As far back as 1965 when living in New Jersey I ran 5W-20 in my 383 cu in Dodge Polara. Chrysler products in those days were said to have 'soft' crankshafts. In those days I changed oil and filter ever 3000 to 4000 miles and my Dodge ran beautifully never using the tiniest drop of oil,

 

[kschachn]

Film thickness is most certainly a cushion, it isn't about flow. Every engine needs the cushion that the MOFT provides, otherwise there is metal-to-metal contact and failure occurs.

 

[Sequoiasoon]

Many pictures I have seen showed more burnt/varnished areas from the rear bank of the Honda 3.5 V6 as a result of those pistons being shut down by VCM. They also had the issues of coked up piston rings etc on the cylinders that spent "inactive" time.

Honda recommended and did engine rebuilds for ring issues. Others disabled VCM, some good oils/flushes and eliminated the ring issues without rebuild.

 

[dwcars]

Did you know that

What Weight Oil Do Race Cars Use?​

Race cars typically use a very lightweight oil, such as 0W-30 or 5W-30. This helps to reduce the overall weight of the car, and also helps to improve fuel economy. The lighter weight oil also flows more easily at high temperatures, which is important for race engines that operate at extremely high temperatures.

 

[KrisZ]

Race cars typically use a very lightweight oil, such as 0W-30 or 5W-30. This helps to reduce the overall weight of the car, and also helps to improve fuel economy. The lighter weight oil also flows more easily at high temperatures, which is important for race engines that operate at extremely high temperatures.

 

[TomYoung]

So you think that 3 or 4 working cylinders produce same amount of heat as 6 do?

Really? Please, continue, I am listening with a great attention... But could you use technical, not commercial approach?

I'd like the world be *so* simple ;-)

A few posts down somebody suggests that the heat gradient in a VCM engine might be different. That said, timeaux has suggested that the temperature goes down when VCM is activated. This confuses the question of operating temperature and heat. Very different quantities. Heat may decrease in a VCM engine, but temperature should be maintained by the cooling system.

The next question pertains to "macro" effects claimed from oil choice. This is an older BITOG matter, beaten to death, without resolution. Bottom line is that nobody can listen to a car motor and tell you whether it contains 0w20 or 0W30. The idea that a motor oil can make a car sluggish, is also not shown in the real world. Not sure what technical, not commercial means in this context as I can't really find any commercial language or messages in my post.

And on the question of the world being simple, it is. You can run 0W20 or 0W30 in these vehicles until the cows come home and you'll be safe from oil related failure.

 

[kschachn]

Did you know that

What Weight Oil Do Race Cars Use?​

Race cars typically use a very lightweight oil, such as 0W-30 or 5W-30. This helps to reduce the overall weight of the car, and also helps to improve fuel economy. The lighter weight oil also flows more easily at high temperatures, which is important for race engines that operate at extremely high temperatures.

Yes I do.

Did you notice what word isn't used as a benefit?

 

[dwcars]

Walmart is selling Castrol 5w30 European in the stores today for $28..........

Wow~! You can actually save $5 to $8 in maintaining your $50,000+ personal vehicle~! That could really add up over the years at two oil changes each year.

 

[dwcars]

No, the goal of the manufacturer is to get the vehicle through the warranty period (usually up thru a 60k powertrain warranty) without any claims that are on them to fix. After they're off the hook, they generally give two bowel movements about "trouble free service life".

There's zero money to be made on a vehicle that lasts 300k without any problems; partly because nobody would be buying any parts for them, and partly because nobody could afford a vehicle that was engineered well enough to last 300k without problems.

I think that is the sole reason Ford dropped their 4.6 liter V-8 engine. Far too many people were getting over 300K miles out of it and getting very respectable fuel mileage at the same time~! Current '06 Town Car has 260K miles on it, gets 19.6mpg just piddling around town, and gets its oil and filter changed every 10K miles~!

 

[ZeeOSix]

Yet the 40 grade will not go through the tight clearances yet a 20 when cold will

The magic of a positive displacement oil pump never ceases to amaze !

 

[ZeeOSix]

Current or recently built engines have very tight clearances and don't need a cushion, they need lubrication.

When were engines factory built with really large clearances? Riddle: Why can engines use a wide range of oil viscosity per some owner's manuals if the tight clearance between moving parts are "supposedly" so sensitive and critical that they require/need thinner oil for lubrication? Again, the magic of a positive displacement oil pump.

As far back as 1965 when living in New Jersey I ran 5W-20 in my 383 cu in Dodge Polara. Chrysler products in those days were said to have 'soft' crankshafts. In those days I changed oil and filter ever 3000 to 4000 miles and my Dodge ran beautifully never using the tiniest drop of oil,

In terms of lubrication of the crankshaft and rods, the soft component is the journal bearings. What's that got to do with oil burning?

 

[TomYoung]

Did you know that

What Weight Oil Do Race Cars Use?​

Race cars typically use a very lightweight oil, such as 0W-30 or 5W-30. This helps to reduce the overall weight of the car, and also helps to improve fuel economy. The lighter weight oil also flows more easily at high temperatures, which is important for race engines that operate at extremely high temperatures.

Is this supposed to be a joke???

 

[kschachn]

Wow~! You can actually save $5 to $8 in maintaining your $50,000+ personal vehicle~! That could really add up over the years at two oil changes each year.

It’s a very good oil with some significant approvals at a good price.