0w-30???

[daman]

I plan on changing over to my winter oil here in
a couple weeks, my van a '95 Pontiac Trans sport 3800 v6
says to use eather 10 or 5w30.

do you guy's see a problem if i run a 0w30 M1 SL in it,
i have 5qts left from an old stash????

 

[AndyH]

Sounds perfectly fine to me, M1 0w30 sounds like a great oil for a Michigan winter!

 

[ARB1977]

Just started using Amsoil Series 2000 0W30 and so far so good.

 

[toocrazy2yoo]

I'm gonna use Oh-Dubya-Thirty GC, myself!

 

[427Z06]

Quote:

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I'm gonna use Oh-Dubya-Thirty GC, myself!

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I still don't understand why you want to use thicker oil in the winter.

 

[toocrazy2yoo]

well, it's "0W" when it's cold, and somewhere in between in the meantime.

It'll be fine..

 

[harry j]

I have used Amsoil 0w30 for the last 80,000 miles (2000,000 on odo now) in my 1993 Civic. Oil is full at oil change time, no leaks, none burned..........by all means, use the 0w30 oil.

 

[harry j]

OOPS! That's 200,000

 

[daman]

Thanks guy's i think i will,

just wondering because the lowest the manual said is 5w30,
so i wasn't shure if i should or not.

i know i'll feel better when i start it on a 5deg. or
colder morning...

 

[toocrazy2yoo]

Quote:

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well, it's "0W" when it's cold, and somewhere in between in the meantime.

It'll be fine..

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I hope..

 

[Ron AKA]

You'll be fine with M1 0w30.

One thing to keep in mind when comparing oils is that the first number viscosity is not absolute. It depends on the second number. In other words at cold temperatures 0w40 will be heavier than a 0w30, and in turn a 0w30 will be heavier than a 0w20.

So the cold weather purists will choose a 0w20 over a 0w40 any day. And they will get better gas mileage at the same time even when the oil warms up!

 

[WalterMitty]

Quote:

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I plan on changing over to my winter oil here in
a couple weeks, my van a '95 Pontiac Trans sport 3800 v6
says to use eather 10 or 5w30.

do you guy's see a problem if i run a 0w30 M1 SL in it,
i have 5qts left from an old stash????

---

What has always confused me about the oil recommendations from the owners manuals (all makes as far as I can tell) is which number they suggest you change with the temperature.

For the GM 3800 they recommend 5w30 as long as the *high* temperature stays below 100 deg F, but switch to 10w30 if the temp goes over 100 deg F.

Isn't that the wrong number to change? I always thought the first number was the "winter" number and the second was the operating temperature number. Wouldn't it make more sense to change based on the other end of the operating range? I.E. run 5w20 if below 100 max otherwise run 5w30 if over.

Frankly I don't see how an engine with a properly operating cooling system can tell the difference between a 90 deg and a 110 deg day anyway.

This little conflict is what has kept me from trying the lower (e.g. 5w30, 0w30) weight oils. We get many 100+ days around here and sometimes it's hard to time out the changes and the loads so I'm not cruising fully loaded at 80 mph on a day the temp decides to top 100.

Why should I have to worry about the "winter" number on my oil in the warm months when the "warm" number is the same? Unless 0w30, 5w30, etc aren't actually 30 weight oils when warmed up.

 

[mdv]

If were talking synthetics, the difference isn't as big as when we're talking dino.

All 30wt. aren't created equal, they just have to fall within a specified range to be called a 30 wt. The 10w30's tend to be a little more stable at higher temps. than the 5w30's due to their formulations. The manufacturers know that due to the nature of the formulations a conventional 10w30 is going to hold up better for a longer period of time when the ambient temps. hover around 100F.

I would be happy running a syn oil in either weight at those temps no problem. If I ran dino, I would prefer the 10w30 until temps. consistently started dropping into the 50's or so. Of course everyone depends on trip length and load as well.

 

[Dark Jedi]

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well, it's "0W" when it's cold, and somewhere in between in the meantime.

It'll be fine..

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I hope..

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ran GC in my 4.7 V-8 last winter and fired right up in -15F just like it was 70F outside. where as the other dino 5w30 oil you could tell the engine was having troubles with it. the engine was very sluggish at the frist couple of min.

what I just put back in for this winter. as far as gas mileage. its a V-8. good mileage and V-8 dont go together at all. but I have seen no real mileage loss using the thicker GC. guess it can push it just fine.

the elves know what they are doing. dont second guess them. if you try it you might like it

 

[daman]

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The 10w30's tend to be a little more stable at higher temps. than the 5w30's due to their formulations.

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So whats this mean, they don't shear as much as the 5-30's???

 

[toocrazy2yoo]

Jedi..

This 4-banger Hyundai of mine does about 40+ MPG, especially now that we're out of the AC season. I cannot imagine missing whatever mileage 0W30 GC would cost me over M1 5W20. Besides, I already have the GC in stock. I got off the M1 kick when it hit 7.00/qt in my area. They're insane.

Tx!

 

[Blue99]

Quote:

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What has always confused me about the oil recommendations from the owners manuals (all makes as far as I can tell) is which number they suggest you change with the temperature.

For the GM 3800 they recommend 5w30 as long as the *high* temperature stays below 100 deg F, but switch to 10w30 if the temp goes over 100 deg F.

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The property to consider, here, is Noack Volatility.

At high engine temperatures, the lighter hydrocarbon components, in the motor oil, have a tendency to volatize.

10W-30's typically have slightly more of the heavier base oil component in the blend and this yields better Noack numbers and more stability at high temperatures.

This was probably more of a factor for the largely Grp I base stock, GF-2 oils from the late 90's thru early 2000. The Noack rating was 20% vs. the current Noack limit of 15% for GF-4 oils.

A GF-4 5w30 oil, blended from Grp II+ base stocks, tends to demonstrate very good heat resistance.

 

[WalterMitty]

Quote:

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Quote:

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What has always confused me about the oil recommendations from the owners manuals (all makes as far as I can tell) is which number they suggest you change with the temperature.

For the GM 3800 they recommend 5w30 as long as the *high* temperature stays below 100 deg F, but switch to 10w30 if the temp goes over 100 deg F.

---

The property to consider, here, is Noack Volatility.

At high engine temperatures, the lighter hydrocarbon components, in the motor oil, have a tendency to volatize.

10W-30's typically have slightly more of the heavier base oil component in the blend and this yields better Noack numbers and more stability at high temperatures.

This was probably more of a factor for the largely Grp I base stock, GF-2 oils from the late 90's thru early 2000. The Noack rating was 20% vs. the current Noack limit of 15% for GF-4 oils.

A GF-4 5w30 oil, blended from Grp II+ base stocks, tends to demonstrate very good heat resistance.

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My suspicion has been that 5w30 and 10w30 start with significantly different base oils and the add packs are used to hit the numbers.

Going on several years ago (15?) I had heard that a 10w30 may start out with a 30w base and additives would be used to improve low temperature flow. A 5w30 may start out with a 10w oil and viscosity improvers would be used to pass the 30w requirements.

I always thought that single grade oils experienced very little shear, but that the add packs weren't as robust. So, over time and in heavy duty applications, the oil would tend to revert to whatever the base oil had been, and straight 10w (or less) ain't enough to keep bearings apart under load in many engines.

So when I hear about a 0w30 oil, does anybody know what the "base stock" is? If it's a 30w with really boffo flow improvers I can get interested, but if it's a 10w (or less) with a very high add pack, I'm probably not very interested.

 

[Bryanccfshr]

WalterMitty,
Todays Basestocks have a high Viscosity index. Some synthetics can cover the multiviscosity requirements with little or no viscosity index improvers. Even conventional oils have higher VI's todays than they did in the past. Most 0w30's have a very good synthetic basestock to meet the cold temperature requirements.
There are plenty of discussions and technical articles on viscosity to be found in the forums. It will take a long time and alot of reading and searching but the reward is a better understanding of the subject.

This is not a "search Newbie" response.From personal experience I believe you will find it more rewarding if you find the information yourself.

 

[Blue99]

From a viscosity viewpoint, here is the nuts & bolts difference between a basic 5w30 & 10w30 formulation:

A 5w30 is 4-5 cSt base oil plus a small amount of 5-6 cSt plus VI improver to meet the approximately 10.5 cSt @ 100C.

A 10w30 is 4-5 cSt base oil plus more of the 5-6 cSt heavier base and less VI improver to meet the 10.5 cSt target.

Note that the additive pack is adding about 2 cst viscosity to the total to arrive at the final 10.5 figure.