straight grade oil in summer heat okay?

Status
Not open for further replies.
If you already have it, go for it!

But, as noted, I don't think it will be in any way superior, in price or performance, to whatever 1+ gallon container of Dino Oil happens to be on sale at Wally world.

The slightly higher HTHS (vs xW-30) might cost you 0.2 MPG, if that. Looking 5 seconds further down the road while driving will save many times more...
 
I just bought a pail of Mobil 1330 SAE 30 that I will blend with 15W40 1300.
Last summer I blended Duron SAE 40 with 10W30 which results in the same thing.
Duron SAE 30 has been in my 2011 Duramax since last Sept. (83/11.2/3.5)
There are opinions and informed opinions.
I would like to try 20W20 which is 15W20 nowadays, but it is hard to find and
not every oil company offers it.
A SAE 30 may be 100@40C instead of 65@40C like 10W30 is about.
What difference is that going to make in the summer?
 
I already have the best of both worlds.
I'm paid to stay home and paid to go to work.

Last fall there was a discussion started about Amsoil.
Then an East wind off the lake buried Superior Wisconsin with snow
and the topic was put on hold till spring.

Now I can't find the thread.
 
Two issues in this thread:

Oil price (not really a deal)

and is it ok to run. Yes, it is ok to run at higher temps. But as stated (and I agree) why?
 
Originally Posted By: fdcg27
Should you?
Why?

......... It won't hurt anything, but it won't offer any advantages either.


I got 4 cases of 30wt. PYB almost free. I live in TX, drive a older model Chevy pickup (97), and cruise the interstate long distances every day.

The 30wt. PYB works PERFECT for me!
 
Originally Posted By: used_0il
I already have the best of both worlds.
I'm paid to stay home and paid to go to work.


Well I am paid to stay home all the time. Its called a good retirement. Gives me a lot of time to put Amsoil Formula 4-Stroke in my whole house generator (Generac 36 HP V Twin).
 
Last edited:
Originally Posted By: zach1900
In a gas car engine, any benefit or disadvantage?


It's all negative, no advantage.
 
Originally Posted By: tig1
Originally Posted By: zach1900
In a gas car engine, any benefit or disadvantage?


It's all negative, no advantage.


Wrong.

SAE 30wt IS more shear stable, period. You can argue "to what degree?" if you want to, but a straight 30 IS more shear stable.
 
Multi-grade oils are a hack...A very poor hack.
Most 10w30 oils are the "nicest house in the bad neighborhood".

Pennzoil Ultra Platinum 10w30 with its NOACK 5.7 is probably the best house. As refining processes get better, the multi-grades get more "natural"...Less of a hack.

smile.gif


I am running Delo 15w30 in my Subaru right now. Not as smooth as the PHM 10w30 and needs a bit more go-pedal to move.
 
Last edited:
Originally Posted By: used_0il

There are opinions....


Sure, lots. I've even got one, but its a 'best guess' on this and many similar issues.

Originally Posted By: used_0il

....and informed opinions.


Rather few, even here. It'd be quite difficult to have a fully informed opinion on this. You'd need access to lots of actual data, which, if it exists at all, will tend to be proprietary and may be confidential.

There's also, of course, "received opinion", The Big One. Generally the way to bet, but no guarantee.

I wouldn't hold my breath waiting for a definitive answer on this, but "it doesn't matter" would probably do well enough.
 
Last edited:
There is good evidence that the viscosity-index improvers (VIIs) that make an oil multigrade as opposed to straight grade also decrease wear. Most OEMs won't recommend a straight grade in a four-cycle engine but then two-cycle engines usually require straight grade I believe, perhaps because VIIs don't do well in those engines.

This said, this is an older oil chart that shows when you can use 10W, 20W, and 30 straight grades:

da28c55.gif
 
I had no idea the M1 0W-40 I use in my BMW was "a very poor hack", thanks for letting me know. I'm sure with a spread like that it has to be terrible.

Do you have a suggestion for what I should use instead?

Originally Posted By: Lex94
Multi-grade oils are a hack...A very poor hack.
 
Originally Posted By: Lex94
Multi-grade oils are a hack...A very poor hack.

I understand your point, but I see you've taken flak for your wording.
wink.gif
In any case, if you want a worse hack, move up here for a winter, use only monogrades, with no block heater or oil pan heater, and dilute the oil with kerosene to get started. That's a hack.
 
Multigrade oils are believed to have a higher oil-film thickness than single-grade oils for a given HTHS viscosity.

See Page 49 & 50 of the Spearot book for reference.

The reason for this is the viscoeleastic properties of VIIs. So, VIIs not only improve the viscosity index but also the oil-film thickness.

There is no reason to use a single-grade oil in a four-cycle engine unless it's specifically recommended. You will get more wear at normal operating temperature as well as with cold engine, less fuel economy, and poor cold-engine performance.
 
Originally Posted By: Garak
Originally Posted By: Lex94
Multi-grade oils are a hack...A very poor hack.

I understand your point, but I see you've taken flak for your wording.
wink.gif
In any case, if you want a worse hack, move up here for a winter, use only monogrades, with no block heater or oil pan heater, and dilute the oil with kerosene to get started. That's a hack.


Yup...Hence the
smile.gif
in my post.
I know...I am originally from "up there"
smile.gif
 
Man, I'd run it without hesitation. I've often thought of running Delo SAE 30 in my Dakota, but I decided to stick with Defy 10W-40. Around here my options for 30 are Formula Shell, Fred's, Havoline and Castrol. If someone offered QSGB 30 HD, I'd buy a few quarts just to look at them, then I'd probably use them as top off oil.
 
Status
Not open for further replies.

Similar threads

S
Your Opinion on Choosing an Oil Grade
2 3 4
Replies
77
Views
4K
Overfill
Carlostrece
Shell Rotella Gas Truck oil
Replies
18
Views
686
BornSlippy
D
Clearing up common misconceptions with Oil weights
Replies
1
Views
867
Jetronic
O
  • Question Question
Death Valley Drive Using Thin Oil
2 3 4
Replies
64
Views
3K
edyvw
53' Stude
Mono grade oil users
Replies
4
Views
318
Chris142
Back
Top Bottom