Attack of the 10w30s

[Snagglefoot]

I noticed more 10w30 inventory at Wally World. Some folks think it is more shear resistant than 5w30 and therefore more suitable for use in the summer, especially when a 5W Is not really required. Has anyone noticed this this with UOA data? The Kv100 numbers should demonstrate that if it was true.

 

[04silverado6.0]

From my research it is slightly more shear stable, probably wont make a difference. I would say there is no real viscosity difference above freezing. I do like to use 10w30 in vehicles that call for 5w30 year round but it is rare if we see temps under 20* in my part of ky. I do not believe it will make any difference no matter if the vehicle specs 5w30 or 10w30 unless temps are below 0.

 

[Sayjac]

First thought, if Merk was still around he'd be all over this. Oh wait.....

Personally I favor 5w30 over 10w30, but I do use the latter in my lawnmower.

 

[PimTac]

Originally Posted by Sayjac
First thought, if Merk was still around he'd be all over this. Oh wait.....

Personally I favor 5w30 over 10w30, but I do use the latter in my lawnmower.

Merk is here with many different names.

 

[TTK]

Usually less volatility in the 10w-30

 

[Sayjac]

Originally Posted by PimTac
Merk is here with many different names.

 

[csandste]

I certainly believed that in 1994

 

[ammolab]

Strange that folks now worry about 10W-30 or 10W-40 oil in Winter temps.

In the 1970s these were the oils we all put in our cars FOR WINTER. Get me some of that Trop-Arctic man!!

 

[ChrisD46]

Since 10W30 synthetic oils don't have to meet D1 / Gen 2 or I believe SN+ specs - I would tend to think that their add packs might not be as robust as 5W30 weights ?

 

[Audios]

Do any other of Castrols black bottle weights say superior GDI formula? Or is it the 10.30 alone?

 

[Snagglefoot]

Originally Posted by Audios
Do any other of Castrols black bottle weights say superior GDI formula? Or is it the 10.30 alone?


Certainly the 5w30 bottle does.

 

[Buzzinhalfdozen]

Originally Posted by ammolab
Strange that folks now worry about 10W-30 or 10W-40 oil in Winter temps.

In the 1970s these were the oils we all put in our cars FOR WINTER. Get me some of that Trop-Arctic man!!


Been using it in the snowblower and lawnmower!

 

[Linctex]

Originally Posted by ammolab
In the 1970s these were the oils we all put in our cars FOR WINTER. Get me some of that Trop-Arctic man!!


Even into the 80's!

My mom, sister (and others) had newer & nicer cars, so I would put 5W-30 in them for winter (North Dakota saw -40*F often)

But, none of my vehicles were "newer" in the 80's (mostly 60's & 70's vehicles) and I NEVER put 5W-30 in ANY of them because it was "too thin" for them

They still started fine - even with straight 30W

 

[AuthorEditor]

Just make sure you're getting 10W-30 with the ratings you need and want. With the diesel crowd going for 10W-30 now there are a lot of diesel-rated oils available in this weight. But, personally I would stick with what the manual recommends, which is likely a 5W something on most newish cars.

 

[Cujet]

I found better UOA's with M1, 10W-30 in 2 of my Ford trucks (vs 5W-20/30) . However, I've stopped performing UOA's due to my personal belief that overall wear rates are not reflected in the PPM numbers. As plenty of engines need internal work even with good UOA results. BMW bearing failures come to mind, as do Ford's timing chain issues, and GM's balancer chain issues.

Instead, I prefer to choose adequate viscosity for the climate, choose a quality synthetic and change it at the severe service schedule or 5000 miles, whichever comes first.

The only faith I put in UOA results is trend monitoring. A sudden increase in a specific metal, vs the engine's history, may indicate a component failure.

 

[buster]

A 10w30, generally speaking, will have less VII's, which will magnify viscosity loss in the presence of fuel dilution. This is why I recommend a 5w20 for engines that call for a 0w20 but have a tendency to produce a lot of fuel dilution. Volatility is also generally a bit lower. Lower the spread the better in some situations.

 

[DoubleWasp]

Originally Posted by Buzzinhalfdozen
Originally Posted by ammolab
Strange that folks now worry about 10W-30 or 10W-40 oil in Winter temps.

In the 1970s these were the oils we all put in our cars FOR WINTER. Get me some of that Trop-Arctic man!!


Been using it in the snowblower and lawnmower!

The creator must have hated his English teacher.

A lot of people with Jeep 4.0 engines have noted better UOAs with 10w30 than 5w30.

 

[aquariuscsm]

I always use 10W30 in the Mustang vs 5W30.

 

[RDY4WAR]

A 10w-30 will generally have lower volatility and less VII. So long as you're not in too cold of an area, what's not to love?

Also, 10w-30 oils are not less robust. They're usually formulated the same just with less VII and/or heavier base oil. M1 HM 10w-30 is API SN Plus and ACEA A3/B3.