Let's talk religion.

"Rusty Vandura - www.tinyurl.com/keepoppo" (rustyvandura) 02/23/2019 at 13:15 • Filed to: None

0

39

First, about viscosity: a guy at a motor oil company told me some years back that a 10W30 motor oil would be, at a “cool” temperature, behaving like a 10W oil, viscosity wise, but that the cool 10W would still be more viscous than a hot 30W. Does that sound right?

Second, why I ask: I have a ‘91 Corolla with 230k miles on it that puts out a nice puff of blue-white smoke when I start it. Friends who ought to know have told me that this is likely due to worn valve guides or valve seals. 4-AFE or 4-AGE engine; I don’t remember which. Some folks have said that running a straight-weight 30W could help that, or even mixing in a quart of 50W. Where I live, extreme Arctic blast is the mid 30s Fahrenheit .

What are your thoughts?

atfsgeoff > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 13:30

4

Try it during spring/summer when the temp doesn’t fall below 50.

Yes, your understanding is correct. 10W-30 means at cold temp, the oil flows as straight 10 weight oil would at that same cold temp. At operating temp, it flows as straight 30 weight would at operating temp. 10 weight is still far thicker at, say, 20F than even 50 weight at 200 degrees (approximate operating temp) .

facw > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 13:30

0

Your first thing sounds a bit confused? When you have 10W30 that’s 10 Winter weight and 30 weight (not 10 weight and 30 weight). Winter weights and normal weights are not directly comparable. As I understand it  while 10W will be thinner than 1 5W in cold temperatures, 10W30 will still be much thinner  at operating temperature than when cold, even though 10 is less than 30.

farscythe - makin da cawfee! > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 13:39

2

i think oil are great it are make things work gud....

Rusty Vandura - www.tinyurl.com/keepoppo > atfsgeoff 02/23/2019 at 13:40

0

Now, the below 50 consideration: is that going to mean further wear to the engine, or just more resistance to starting? Like I said, a start below 50 degrees would be rare and the extreme of cold is about 35 degrees.

What about using a 10W40 oil? I have half a case of that in the garage from I-don’t-know-when.

gettingoldercarguy > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 13:41

1

Yes, that’s pretty accurate. Try running this through your Corolla, it seriously helps.

https://www.auto-rx.com

After running that, try running rotella t6.  A budget diesel oil that performs very well.

atfsgeoff > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 13:45

0

More resistance to starting and more engine wear.

Something like 90% of internal engine wear occurs within the first minute of cold starts. Running straight 30 weight, I would not want to cold- start the engine in less than 50F ambient temperature.

gogmorgo - rowing gears in a Grand Cherokee > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 14:05

0

I don’t know that it will have a significant effect. The oil is most likely to run down worn valve stem seals while the engine is still warm. There’s a chance you’ll see a small benefit to stepping up to a 10w40, but let’s face it, there’s mechanical damage to the engine causing the oil to entre the combustion chamber in quantity , and the only way to re solve the problem is by replacing the worn components. 

Daily Drives a Dragon - One Last Lap > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 14:33

3

I say your religion is wrong and we should have a war. 

gettingoldercarguy > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 14:41

0

You’d be fine with the 10 or even a 15w oil in startup. The times you’ll see for oil pressure to develop even at the end of the circuit will be negligible. Thin oil is for fuel economy in a bogus test standard that nobody ever sees practically. It’s the same bs of turbo truck engine achieving better fuel economy in these tests, then real world is worse.

Look at the oil viscosity recommended in Europe for the same engine. Almost always a grade thicker. A couple of great tribologists and pet ro engineers I know in Australia have substantive evidence that in climates such as yours, a thicker oil consistently wears less, even during startup as it doesn’t drain down like near water weights.

gettingoldercarguy > facw 02/23/2019 at 14:48

0

Nah, his info is good. It’ll behave like a 10 weight in cold cold temps, but a 30 right at operating temperature. The way that oil viscosity  responds to temperature means that a cold 10 is thicker than a hot 30.

gettingoldercarguy > gettingoldercarguy 02/23/2019 at 14:58

1

I meant to say turbo truck engines achieve better economy in the standardized test than naturally aspirated, larger engines.  But in the real world the bigger engines are more efficient.

facw > gettingoldercarguy 02/23/2019 at 15:05

1

The way that oil viscosity responds to temperature means that a cold 10 is thicker than a hot 30. 

I think that’s what I was saying?

gettingoldercarguy > facw 02/23/2019 at 15:07

0

Crap, reading comprehension fail.  You're right, sorry.

Urambo Tauro > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 15:12

0

Did I kn ow you had a ’91 Corolla? Maybe I forgot. My mom has a ’90 (4A-FE) , and while I’m by no means a Corolla expert, I did have some interesting wrenching adventures with it last year (n othing particularly engine- oil-related, though).

ITA97, now with more Jag @ opposite-lock.com > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 15:15

1

That understanding of how oil behaves cold vs. hot is correct. There’s certainly some old school merit to eventually running a thicker oil in older engines. The idea is a thicker oil film being a good thing with the increased bearing clearances of a worn engine. Oil weights have gotten generally lighter with time due to both advancements in viscosity modifiers, and CAFE standards. Most engine wear occurs at startup, so there’s a benefit to a thinner oil getting circulated to bearing surfaces sooner on a cold start. Fractional gains in fuel economy across fleets maters. Bearing clearances inside motors haven’t really changed in the last 60 years outside of some exotic race car stuff.

10w- 30 is an oil weight there isn’t a good reason to really run anymore, as viscosity modifiers as 5w-30 has largely replaced it. Better cold flow characteristics, with basically the same high temperature characteristics. I would not run a straight weight oil in any modern engine outside of break-in .

For the car and use case you describe, I’d probably be running a 10w-40 in it at this point, and would probably at least consider running a 20w-50 in the summer. Mobil O ne’s 15w-50 wouldn’t be a bad choice either, but unless that motor had run been running synthetic for most of its life anyway I wouldn’t start at this point.

gettingoldercarguy > ITA97, now with more Jag @ opposite-lock.com 02/23/2019 at 15:18

0

I’m suggesting Rotella t6 after a run of auto rx. I’d love to pull the valve cover for a before and after.

The t6 is great and more budget friendly. He can use that additional can towards a better filter and the auto rx.

10w30 has some fantastic hths numbers and typically lower burn off rates than a 5w. So it’s “ better” for bearings and won’t gum up the house as quickly as a 5w

Rusty Vandura - www.tinyurl.com/keepoppo > farscythe - makin da cawfee! 02/23/2019 at 15:29

2

I love you because you are always so helpful.

Rusty Vandura - www.tinyurl.com/keepoppo > gettingoldercarguy 02/23/2019 at 15:31

0

Due diligence: you are serious about the oil treatment? It's not snake oil?

Rusty Vandura - www.tinyurl.com/keepoppo > atfsgeoff 02/23/2019 at 15:32

0

What about running 10/40 or 15/40?

gettingoldercarguy > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 15:33

0

It’s absolutely not snake oil. Read up on it. It works, and works well.

Rusty Vandura - www.tinyurl.com/keepoppo > gogmorgo - rowing gears in a Grand Cherokee 02/23/2019 at 15:33

0

Yes, I understand that. I’d love yo rebuild the engine, but the transaxle is showing its  age as well.

Rusty Vandura - www.tinyurl.com/keepoppo > Daily Drives a Dragon - One Last Lap 02/23/2019 at 15:34

1

*sighs*

farscythe - makin da cawfee! > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 15:36

1

here to help mate you know me :)

atfsgeoff > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 15:37

0

You can try 15/40 if your goal is to reduce oil consumption.

Rusty Vandura - www.tinyurl.com/keepoppo > gettingoldercarguy 02/23/2019 at 15:38

0

II am certainly game to try the rotella 15 w 40. I just want to be reassured about the additive you mentioned.

Rusty Vandura - www.tinyurl.com/keepoppo > atfsgeoff 02/23/2019 at 15:39

0

I will try it. Consumption really is not the issue, rather, smoke at startup. Really does not seem to use much oil.

atfsgeoff > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 15:45

0

Time to roll up your sleeves then. Run compression test first to eliminate piston rings as culprit.

gettingoldercarguy > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 16:01

1

Yeah, if you are on Bob is the oil guy, look for a guy by the name of molakule and his take on it. He’s the only person still on there I’d trust. There’s a ton of signal to noise anymore on that forum with a bunch of unqualified obtuse people making replies on subjects they have no business doing.

gettingoldercarguy > farscythe - makin da cawfee! 02/23/2019 at 16:02

0

Yeah, but what's your take on vaccines?

farscythe - makin da cawfee! > gettingoldercarguy 02/23/2019 at 16:05

1

if you didnt have any stay the fuck away from me?

jimz > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 16:15

0

rotella 15w40 is also likely to have more ZDDP (an anti-wear) additive than other oils.  ZDDP content is being lowered as much as possible since phosphorus is a catalyst poison.  On a car with the mileage yours has, I doubt that’s much of a concern.

jimz > Daily Drives a Dragon - One Last Lap 02/23/2019 at 16:16

1

if you want that then bobistheoilguy.com is the usual battleground.

Highlander-Datsuns are Forever > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 16:39

1

Back in the old days on a high mileage engine we would run 10w 30 in the winter, and 20w 50 in the summer. Summer being may-September and temperatures routinely go below 30 during that time in Montana.

gogmorgo - rowing gears in a Grand Cherokee > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 16:45

1

Mechanical damage in this case really only means worn out seals. In many cases you don’t even need to pull the head to change the valve stem seals. The difference in weights of oil isn’t going to do much, despite what people will tell you. If it was me, I’d leave it alone though TBH, unless there’s huge oil consumption associated with it. On a new car you’d be hard pressed to get a warranty repair if  its burning less than a quart every 750 miles.

My bird IS the word > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 20:15

0

I think you should only use conventional oil because synthetic breaks your engine. The internet told me so.

Rusty Vandura - www.tinyurl.com/keepoppo > jimz 02/23/2019 at 20:37

0

I’ve got some 10W40 in the garage and we’ll just use that and I’ll fugettabatit for another 5,000 miles.

Rusty Vandura - www.tinyurl.com/keepoppo > gogmorgo - rowing gears in a Grand Cherokee 02/23/2019 at 20:39

0

My sister-in-law had a Ford Aerostar that used a quart every 500 miles. Ford said that was within their acceptable limits and refused to do anything for her about it.

Rusty Vandura - www.tinyurl.com/keepoppo > My bird IS the word 02/23/2019 at 20:41

1

gogmorgo - rowing gears in a Grand Cherokee > Rusty Vandura - www.tinyurl.com/keepoppo 02/23/2019 at 21:10

1

I didn’t really want to paint a wash over all manufacturers. I’ve only experienced (second hand) Subaru denying 1L/1000km, and I over heard something similar in line at a GM parts counter, one customer to another.  Ford being dickish doesn’t surprise me much either.