Anyone using 10w40 or obsolete?

[Corollaman]

Anyone using 10w40 in an older V8 engine? Would a high milage oil 10w40 oil hold it's viscosity better than a conventional 10w40?

 

[Dyusik]

1) no
2) surely someone
3) yes

10w40 is a widely used moto spec, higher VI of syn base stack, less VII to shear.

 

[SilverFusion2010]

Today's 10w-40 is going to be tougher that the old stuff. You might consider one of the thick 10w30, or a Full Synthetic 5w-40. Are you sure you need SAE 40?

 

[BironDanmum]

I still run it in my motorcycles. The last two cars I had that were spec'd for it (1975 Coupe Deville and 1982 Granada) were sold about 10 years ago, so not since then.

 

[Oro_O]

Good point, OP. One reason I run Mobil 1 10w30 High Mileage in some vehicles is that the HTHS is 3.5, vs 3.0 for the "plain" Mobil 1 10w30. I know the HTHS of the 10w-40 High Mileage is 3.9; I use that in one vehicle and will switch another to it later this year (in fact an older - 1991 - V8). The HTHS value is a proxy for shear stability, not a perfect indicator.

 

[c502cid]

I use it for everything that isn't new and under warranty. If any are driven in the winter I drop down to a 5w30 or 5w-40 depending on the application.

 

[Garak]

What would a 10w-40 accomplish that a 10w30 HDEO wouldn't?

 

[B320i]

When I did the oil change on families' HJ Holden Monaro (Australian 253 V8), the manual called for xW-30, xW-40 or xW-50 depending on climatic conditions. Chose 10w40; as I could get that grade in Semi-Synthetic from Penrite at a decent price - plus it has the high-zinc additive packs.

Penrite no longer seem to give HTHS information for their products, but being A3/B4, it should be fine.

 

[userfriendly]

Every now and then I will buy a 20L pail of Duron 10W40. It flows 'n pumps like a 5W40, but a little harder to crank over. HTHS in the CK-4 offering is >4.10 and it carries many builder approvals.

www.lubricants.petro-canada.ca

Any other synthetic 10W40s out there?

 

[Alex_V]

I flop back and forth between 10/30 and 10/40 in my '72 Honda motorcycle, and run Valvoline 10w40 conventional in my '67 Suburban. No doubt a quality 10w30 will do just as well in most applications, but I chose 10w40 for the 'Burb to have a little better protection without the cost of a more expensive oil.

 

[SilverFusion2010]

I'd go for a thicker 10w30 like Mobil 1 High Mileage. Unless you're running temps that are thinning the oil or dealing with fuel dilution I don't see a good reason to go 40 in a gasser

 

[jongies3]

Nah, I don't see the point when 15w40 is more widely available. I run it in all my old flat tappet V8's because of the high zinc, plus, something about running a HDEO in an older engine makes me feel warm and fuzzy for some reason.

 

[BrocLuno]

I run 15w40 in high mileage vehicles that like to rattle the rod bearings on cold start. Usually quiets them down quick. So, right now, that's only one - Big Bronco with close to 220K on the clock

 

[FlyPenFly]

I'm switching to a Red Line 10w40 in my DFI Porsche. Temps don't go below 50F where I live.

It should be more shear stable.

 

[FCD]

In an older V8 a 10w30 or 15w40 HDEO would be better.

 

[SR5]

I've used a bit of GTX 15W40 mineral oil, it's a common grade around here. The GTX is spec'd API SN and ACEA A3/B3. My GM car owners manual says to use a 10W30 or 15W40 oil in A3/B3 or the higher A3/B4, so the GTX is bang-on for my car. It's a GM / Holden / Opel and no API spec is given in the OM.

Anyway, I've noticed a local Oz oil company, Nulon, make a full synthetic (Group III) 10W-40 that is API SN and ACEA A3/B4 plus a few Euro OEMs like MB 229.3 and VW 502/505. I sometimes see this oil at a good price, and it's 100 C viscosity is very similar to the GTX. I know the GTX 15W40 has a HTHS of 3.95 cP with a KV100 = 14.5 cSt, a TBN of 8.3 and CCS at -20C = 6700 cP

I may spend a bit more coin next time and treat my car to a full synthetic 10W40, and maybe run it a bit longer.

Nulon 10W40 Synthetic (SN, A3/B4, MB229.3, VW502/505)
KV100 = 15.07 cSt
SA = 0.9 %
TBN = 9.8
CCS at -25C = 5270 cP
Plus a big slug of Molybdenum Dithiocarbamate, which is Nulon's special not-so-secret sauce.

Not saying it's the best oil in the world, but the GTX 15W40 mineral always works for me, and the 10W40 synthetic just looks a bit stronger in most of the common metrics.

 

[bullwinkle]

I'm still using Valvoline Next Gen Max Life 10W40 in the XJ 4.0 in my sig, approaching 230K with virtually no consumption & decent hot idle oil pressure. If the mild winters continue I may stop swapping in the winter 10W30. Back in the day, we ran that 10W40 [censored] in EVERYTHING!

 

[fdcg27]

We also ran that "stuff" in everything back in the day with never a problem.
The 10W-40s from back in the day were typically lower HTHS oils than is true today FWIW.
I've also have some jugs of Next Gen Maxlife 10W-40 left from the summer of FAR deals on it.
This will be the next fill for my old E350.

 

[Triton_330]

Originally Posted By: Corollaman
Anyone using 10w40 in an older V8 engine? Would a high milage oil 10w40 oil hold it's viscosity better than a conventional 10w40?


Today's 10w-40s and leaps and bounds ahead of the stuff used decades ago.

Anyway, what specific vehicle are you asking about? Because if you aren't asking for a specific vehicle, no good advice can be given.

 

[FCD]

Here in Spain 10W-40 Synthetic blends are the one size fits all for anything with a gasoline engine that is over 15 years old.
So there is no reason not to use a good 10W-40, not even 20W-50 is obsolete, it is still used in millions of cars all over the world, including my 2

.