Any reason not to use 5w-30 in place of 10w-30?

Status
Not open for further replies.
Joined
Mar 31, 2010
Messages
6,258
Location
Iowa
The other day, I was working on the boss to convert back to bulk oil, (from cases of quarts) citing environmental concerns and convenience. We briefly discussed what we'd stock and I suggested just having 5w-20 and 5w-30 in drums. Is there any concern using 5w-30 in place of a 10w-30? With today's modern base stocks and additive packages, I can't see why a 5w-30 wouldn't hold up in place of a 10w-30...

FWIW, the oil in question would be Kendall GT-1 Synthetic blend with the Liquid Titanium.
 
In Iowa 5W30 would be fine year round for any car using 10W30. I prefer 10W30 for mine, though 5W30 is fine for fall and winter, but that's only because it burns oil and the 10W30s I have are more resistant to burn off than their 5W30 counterparts (not due to thickness as both are the same at operating temp).

-Spyder
 
I don't know about completely replacing 10w-30 since some customers may insist on it. Perhaps keep some in quart cases?

Practically, 10w-30 is better in cases where shear is a concern and for some direct injection applications but for the most part, 5w-30 shouldn't be a problem.
 
If you look at NOACK limits for SM/GF-4 compared to previous specs just a few years back (SH/GF-2), modern 5w-30 conventional oils would far surpass a 10w-30 of yesteryear. Given you'd be using The Kendall blend, I'd have no problem doing what you want to do. I bet the cost savings alone would be justifiable.
 
Last edited:
I'd also go with the 5-30 instead.
10-30 is kinda obsolete.
Oils are tougher and more well built now. Shearing is rarely a real life concern.
 
Great, thanks for your input! It more or less confirm my thoughts all along.

Now the tough part will be selling it to the boss. Granted it's not necessarily a bad thing, but if an oil cap calls for 10w-30 (like an older GM 3.8), then that's what goes in it unless it's winter time. Unless a customer asks for or supplies something different, it's strictly by the book/cap. The only thing is that some of those specs are outdated as many of you already know.
 
Last edited:
Originally Posted By: mechtech2
I'd also go with the 5-30 instead.
10-30 is kinda obsolete.
Oils are tougher and more well built now. Shearing is rarely a real life concern.


agreed 100%
 
5w30 will hold up, but if you never even see freezing temps, what's the point? (Obviously not the pour point- flashpoint maybe) Unless you can be assured the 5w30 is formulated with a higher VI base stock than the 10w30, which can happen, why bother? Generally, I find most big oil blenders don't like to keep more basestock grades on hand than absolutely necessary, and 10w30 to be a more robust oil lacking only in VII content to it's 5w30 counterpart. There are a lot of old ways of thinking that are just obsolete these days, but honestly, 10w30 in warm climates is not one of them IMO.
 
Originally Posted By: ItsuMitsubishi
5w30 will hold up, but if you never even see freezing temps, what's the point? (Obviously not the pour point- flashpoint maybe) Unless you can be assured the 5w30 is formulated with a higher VI base stock than the 10w30, which can happen, why bother? Generally, I find most big oil blenders don't like to keep more basestock grades on hand than absolutely necessary, and 10w30 to be a more robust oil lacking only in VII content to it's 5w30 counterpart. There are a lot of old ways of thinking that are just obsolete these days, but honestly, 10w30 in warm climates is not one of them IMO.


First off, we definitely see freezing temps! Secondly, it'll be tough enough to get him to switch to 5w-30 for both applications, there's no way he'll go for 10w in a 5w application. I think he's one who doesn't know terribly much about oil, so 10w is thicker to him than 5w.
 
Originally Posted By: The_Eric
Originally Posted By: ItsuMitsubishi
5w30 will hold up, but if you never even see freezing temps, what's the point? (Obviously not the pour point- flashpoint maybe) Unless you can be assured the 5w30 is formulated with a higher VI base stock than the 10w30, which can happen, why bother? Generally, I find most big oil blenders don't like to keep more basestock grades on hand than absolutely necessary, and 10w30 to be a more robust oil lacking only in VII content to it's 5w30 counterpart. There are a lot of old ways of thinking that are just obsolete these days, but honestly, 10w30 in warm climates is not one of them IMO.


First off, we definitely see freezing temps! Secondly, it'll be tough enough to get him to switch to 5w-30 for both applications, there's no way he'll go for 10w in a 5w application. I think he's one who doesn't know terribly much about oil, so 10w is thicker to him than 5w.


Whoops, yeah I checked your locale after I posted that. I thought it was for California or something. Indeed 5w is certainly the grade for your bud :)
 
Any reason not to use 5w-30 in place of 10w-30 ?

Yes, the reason is Honda only specified 2 weights for S2000, for temp above 0F use only 10W30 and for temp below 0F use 5W40.

Why Honda recommend 5W40 in S2000, not 5W30, for temp below 0F is a mystery to me. For an engine that can rev to 9k RPM, 10W30 is more shear stable therefore it is recommended.
 
Originally Posted By: HTSS_TR
Any reason not to use 5w-30 in place of 10w-30 ?

Yes, the reason is Honda only specified 2 weights for S2000, for temp above 0F use only 10W30 and for temp below 0F use 5W40.

Why Honda recommend 5W40 in S2000, not 5W30, for temp below 0F is a mystery to me. For an engine that can rev to 9k RPM, 10W30 is more shear stable therefore it is recommended.


Bump: Honda needs the car to perform and rev like crazy in sub 0* temps too! The car requires a shear stable oil at lower temps. 10w-30 is not adequate for cold temps. 5w-30 is not shear stable enough. So 5w-40 works with cold temps, shear stable since its synthetic and is thicker to deal with the fuel dilution that winter driving creates.

Smart decision Honda.
 
Originally Posted By: 901Memphis
Even since this thread was made in 2010 I'm sure 5w30s are even more shear resistant than before.


I agree, you could also argue that 5w-30 has come along way since the S2000 came out in 1999
wink.gif
 
I would agree with others that 10W30 is kind of obsolete, although I wouldn't mind using a 10W30 in place of 5W30 in a pinch specially during summer. I think you do have an issue with customers potentially insisting on having a 10W30. How many will insist on it? Perhaps you could stock a little 10W30 in quarts just for them?
 
Since the 10W-30 grade is no longer specified by any company I wouldn't stock it at all. If some old school thinking customer requests it simply educate them that a 5W-30 synthetic will provide more high temp' protection than a 10W-30 dino.
If I was to keep any heavier oil on hand it would be a 0W/5W-40 so that a blended heavier 5W-30 option is available if not an outright high VI 40wt.
 
Status
Not open for further replies.
Back
Top