10w30 SO WRONG???

[Timothy Ferguson]

Why is it ok to use 5w30 in a car or truck or mini-van that specs 5w20 why can't you use 10w30. Everyone I speak to around here says don't worry about using 5w30 in any automobile thats specs 5w20 but never what so ever use 10w30. WHY? Aren't you worried what weight the oil will be when hot? 5w30 and 10w30 are all 30weight oils when hot correct??? I understand if you wanted to use a 40weight oil may be to thick. So you don't want to use that. If 10w30 is so thick at start up why is it ok to use it in my ranger that specs 5w30????

edit for spelling - BTW, I use Chevron 10W30 in South Georgia and have had great UOA results - joe

[ March 20, 2005, 02:10 PM: Message edited by: joee12 ]

 

[TomJones76]

Mr. Ferguson,

If temperatures are above freezing, 10W30 will be fine in any car that specifies 5W30.
If anyone tells you anything different, ask for a citation from a refereed academic journal published in the mechanical engineering field.
They won't have one.
Now if you decide you want to take your Georgia car up north to visit a Yankee friend in Vermont for Christmas, you probably ought to not leave 10W30 in the crankcase.

 

[Timothy Ferguson]

Thats great to know. Thanks. But what about the question about using 10w30 in a car that specs 5w20?

 

[andrews]

In my opinion (no data from any scientific institute) I would stay with what the manual states. While using 10w-30 instead of 5w-20 may not have any noticed effect, long term use may be different. There was a thread on here somewhere where a guy with a background on the subject, stated that one of the most critical aspects of a motor oil was it's ability to flow quickly at start up. Many opinions about this issue exist all over this board, but I'll stick with the one that seems the most common sense to me. A 5w oil will flow faster, and easier, into the far reaches of a cold engine, slightly better than a 10w oil. The gentleman mentioned earlier also stated that it made no difference if you lived in Florida or Montana, a 5w oil is a wiser choice for less start up wear.
Why not just use a 5w-30 instead of a 10w-30.....since the 5w-20 seems to bother you?
Just my opinions, take it as you wish.

 

[crossbow]

Or even better...why not a 0w-30..such as the Green Elixir! (See entire forum dedicated to it)

I think most people are under the impression that 5w-20 doesn't protect the engine, which is why people are always posting questions (is 10w-30 ok?). Well 20 wt oils protect just dandy...so stop worrying already.

 

[Triple_Se7en]

I'm not a firm believer that the heat of Georgia should see a ?W-20W oil year-round. I would opt for the 5W-30.

 

[jorton]

This is an important topic to me because I have 10w-30 in my f150 now. I did notice it was (not quite)thin like water when I poured it in the motor. At the time the oil was about 80 degrees because I warmed it up on the heater vent in the house.

I think climate affects viscosity choice because here temps will be warm for the next 7 months.

[ March 20, 2005, 11:36 AM: Message edited by: jorton ]

 

[John in the ATL]

Timothy,

I believe the recommendations in the manual for US and Japanese cars are dumb down and have a bias for CAFE standards. If you look at older manuals and check websites for the same cars sold abroad, they spec oil weights based on ambient temperature. Mobil 1 has renamed their 0w-20 as 5w-20 since most people were confused by it not saying exactly what the manual spec'd.

To directly answer your question, I prefer 10w-30 to 5w-30 since I believe it to be more shear stable. I am going to be running a 10w-30 Mobil 1 or Schaeffer's in a 2004 Odyssey spec'd for 5w-20 through late spring and into the fall. I will let you know how it goes. Based on our ambient temperatures, I think this is the best course of action.

There is nothing wrong with running Xw-20 from November through March and Xw-30 the rest of the months.

 

[ToyotaNSaturn]

Really any oil is fine to use up to 50wt. While the 50wts will bring downt the MPG, they wont kill the engine either.

Yes, it's perfectly fine to run 10w-30 in a car that calls for 5w-20. I wouldn't run any 10w-30 dino below 0F personally. But most bulk oil is 10w-30 from Nome (AK) to Rome (GA) anyway.

The afforementioned CAFE requirments are the main reason why we see "use only 5w-20..." in our owners manuals. It's completely safe to use 10w-30. Your choice of Delo 10w-30 is a great choice!

 

[Blue99]

quote:

---

Yes, it's perfectly fine to run 10w-30 in a car that calls for 5w-20. I wouldn't run any 10w-30 dino below 0F personally. But most bulk oil is 10w-30 from Nome (AK) to Rome (GA) anyway.

The afforementioned CAFE requirments are the main reason why we see "use only 5w-20..." in our owners manuals. It's completely safe to use 10w-30. Your choice of Delo 10w-30 is a great choice!

---

I agree entirely with all of ToyotSaturn’s statements.

As far as a 5W oil being necessary for start-up protection, reference the viscosities listed below for 5W & 10W-30 Havoline.

code:

---

Temperature Havoline Viscosity in cSt

C F 5W-30 10W-30

0 32 573 814

5 41 403 556

10 50 293 389

15 59 218 280

20 68 165 206

---

Consider this example:

The author of this thread, Timothy Ferguson, starts up his Ford Ranger, with 10W-30, in Newnan GA, tomorrow morning with an outside temp of 50 degrees F.

I start up the exact same vehicle, with 5W-30, in Milwaukee WI, tomorrow, with the temp at 32 degrees F.

Due to the temperature differential, my start-up viscosity with the 5W-30 is 573 cSt. Timothy’s 10W-30 start-up viscosity is 389 cSt. His 10W-30 is actually thinner than my 5W-30 due to the temperature.

So these statements regarding always use a 0W or 5W for start-up protection fall apart, as the reasoning fails to factor in the effects of temperature on viscosity.

 

[Drew99GT]

quote:

---

Originally posted by Blue99:

quote:

---

Yes, it's perfectly fine to run 10w-30 in a car that calls for 5w-20. I wouldn't run any 10w-30 dino below 0F personally. But most bulk oil is 10w-30 from Nome (AK) to Rome (GA) anyway.

The afforementioned CAFE requirments are the main reason why we see "use only 5w-20..." in our owners manuals. It's completely safe to use 10w-30. Your choice of Delo 10w-30 is a great choice!

---

I agree entirely with all of ToyotSaturn’s statements.

As far as a 5W oil being necessary for start-up protection, reference the viscosities listed below for 5W & 10W-30 Havoline.

code:

---

Temperature Havoline Viscosity in cSt

C F 5W-30 10W-30

0 32 573 814

5 41 403 556

10 50 293 389

15 59 218 280

20 68 165 206

---

Consider this example:

The author of this thread, Timothy Ferguson, starts up his Ford Ranger, with 10W-30, in Newnan GA, tomorrow morning with an outside temp of 50 degrees F.

I start up the exact same vehicle, with 5W-30, in Milwaukee WI, tomorrow, with the temp at 32 degrees F.

Due to the temperature differential, my start-up viscosity with the 5W-30 is 573 cSt. Timothy’s 10W-30 start-up viscosity is 389 cSt. His 10W-30 is actually thinner than my 5W-30 due to the temperature.

So these statements regarding always use a 0W or 5W for start-up protection fall apart, as the reasoning fails to factor in the effects of temperature on viscosity.

---

THANK YOU Blue99!!!!!! I keep trying to point out that you're not gaining anything regarding cold start flow with 5w-30 when it's summer

If you have 10w-30 in your vehicle and start it when it's 80 degrees F outside, your oil will be thinner than if you start it with 5w-30 when it's 10 degrees F outside. Why anyone thinks your gaining ANYTHING by running 5w-30 in above 60 degree weather is beyond me.

 

[Ken2]

Here in our mild-winter coastal northwest climate, the county maintenance shop runs 10W-30 in all the sheriff's Crown Vic cruisers. The foreman tells me that he has no engine failures while shops in nearby counties use 5W-20 and have a few engine failures.


Ken

 

[Kestas]

Considering what the cops do to these engines, this difference could be significant.

 

[farrarfan1]

Doesn't that Havoline chart prove that 5W provides faster startup flow than 10W at all the temeratures listed? It may not be significant but the 5W will get to the top end faster than the 10W even in the summer.

 

[Drew99GT]

quote:

---

Originally posted by farrarfan1:
Doesn't that Havoline chart prove that 5W provides faster starup flow than 10W at all the temeratures listed? It may not be significant but the 5W will get to the top end faster than the 10W even in the summer.

---

Yes, but how much faster is it going to flow when it's 80 degrees F? It's probably immeasureable. I still think 10w-30 will provide better protection in extreme heat. A few OEMs still recomend 10w-30 for temps over 0 F and 5w-30 only under 60 F.

 

[farrarfan1]

In the VOA section there is a compendium of VOA's from 2003 that show Mobil1 0W30 and 5W30 are both thicker at 210F than the 10W30. The VOA posted by Stinky Peterson on the SM GF-4 Mobil1 also shows the 5W30 is thicker than the 10W30 at 210F.Just because it has 10W at the beginning doesn't always mean it's viscosity is thicker at operating temp than 5W.I'd rather have a little thicker viscosity at operating temp in hot summer temps and a little quicker startup flow. GC 0W30 is around 12 cst at operating temp.I think a lot of the opinions about 10W being better in the summer are based on "feelings" rather than the actual property of a given oil. IMHO of course.

 

[Pablo]

Kinda along the same line of my synthetic 15W-40 is very fine in temperate and above winters theory.

You'll be fine!

 

[Drew99GT]

quote:

---

Originally posted by farrarfan1:
In the VOA section there is a compendium of VOA's from 2003 that show Mobil1 0W30 and 5W30 are both thicker at 210F than the 10W30. The VOA posted by Stinky Peterson on the SM GF-4 Mobil1 also shows the 5W30 is thicker than the 10W30 at 210F.Just because it has 10W at the beginning doesn't always mean it's viscosity is thicker at operating temp than 5W.I'd rather have a little thicker viscosity at operating temp in hot summer temps and a little quicker startup flow. GC 0W30 is around 12 cst at operating temp.I think a lot of the opinions about 10W being better in the summer are based on "feelings" rather than the actual property of a given oil. IMHO of course.

---

Look at HT/HS values of those same oils. Measure their viscosities after being used for a while. Especially with dino 5w-30s, compare viscosities with dino 10w-30s after use. Did you ever think to consider that some 5w-30s run a higher viscosity at 100C because the manufacturer built that in knowing it will thin more than the 10w-30, on average? Are you telling me that 5w-30 is BETTER in hot temps because it may be a hair thicker when virgin, even though it has a lower HT/HS and has a proven tendancy to thin?

 

[Blue99]

quote:

---

I think a lot of the opinions about 10W being better in the summer are based on "feelings" rather than the actual property of a given oil. IMHO of course.

---

Farrarfan1 - IMHO opinions are always welcome on this forum!

I think the key issue when comparing 5W to 10W-30's is Noack Volatility. The higher viscosity base oils, by nature, have a lower volatility rating. The 10W-30's will have a greater % of higher viscosity base oils in the blend and this allows less burn-off during high engine temperatures as commonly encountered during warm summer weather.

We saw this in many of the dino 5W-30's going to all GRP II, GRP II/III blends, and all GRP III to pass the 100 hr SEQ IIIG test for GF-4.

As to the virgin 5W-30's showing slightly higher viscosities at 100C than a 10W-30, run these oils for 1K miles and then re-test. The VI improvers in the 5W-30's will have already started to shear. The majority of UOA's for dino 5W-30's have a lower SUS than the 10W-30's for the same brand.

 

[andrews]

It would seem that the start up viscosity is more important, in how it relates to wear, than the operating temperature viscosity. (Within reason, of course).