Any synthetic 5w30 or 10w-30 that act like a 40wt?

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I've always used Mobil 1 synthetic and usually mix 4qts. of 10w-30 with 2qts. of 15w-50 to thicken up the viscosity a little. I have a 1999 Jetta GLX (A3) VR6 and my oil temps run close around 242F in the summer with AC on when running 80-85mph on the highway. Are there any synthetic 5w-30 or 10w-30 oils which are naturally a "heavy" 30 weight or even approach a 40 weight? Thanks for any recommendations.
 
Yes, Amsoil 5w30 and 10w30 are both very close to being 40wts.

As well, German made Castrol Syntec 0w30 is very close to being a 40wt too.

And even though Redline's technical data shows it's more of a middle 30wt, in reality their 5w30 and 10w30 are upper 30wts also.
 
Wouldn't a lighter weight oil run cooler? It would flow faster than a thick one. A thicker oil generates more heat because of the friction it has to overcome.
 
quote:

Originally posted by JonS:
Wouldn't a lighter weight oil run cooler? It would flow faster than a thick one. A thicker oil generates more heat because of the friction it has to overcome.

That has been my experience. Running oil that is heavier than required is a fast way to high oil temps...
 
quote:

Wouldn't a lighter weight oil run cooler? It would flow faster than a thick one. A thicker oil generates more heat because of the friction it has to overcome.

Probably. The whole idea that you need a thicker 30wt oil or heavier oil perioed is bogus. You need to match the right viscosity with the engine, in which many cases it varies. All engines seem to have there preferred grade of oil if one does a UOA on them. When is the last time you heard someone have an engine problem that was related to oil? Exactly. Other then sludge, it's not too common.
 
When I owned a VR6 engined VW it recommended 15w-40 in winter and 20w-50 in summer (1995)
I think the winter recommendation is now 5w-40 ( dont know if the sumemr recommendation changed as well).

Why are you running thinner oils?

Fred..
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The thinner oil will lower the temps, but only about 10F lower--which is still pretty high
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. The VR6 is a VERY hot running engine, no doubt about it. I've always felt the VR6 is a canidate for a slightly thicker grade than a 30wt because of the high temps.

Anyways, what specs should I be looking for to determine if an oil is close to a 40wt? And what is the upper and lower ranges of a 30wt and 40wt. oils?
 
quote:

Originally posted by Bobert:
The thinner oil will lower the temps, but only about 10F lower--which is still pretty high
smile.gif
. The VR6 is a VERY hot running engine, no doubt about it. I've always felt the VR6 is a canidate for a slightly thicker grade than a 30wt because of the high temps.

Anyways, what specs should I be looking for to determine if an oil is close to a 40wt? And what is the upper and lower ranges of a 30wt and 40wt. oils?


I think that there is some logic in your thoughts. Also I believe that mixing the two wt oils as you did is a good Idea. I personally do it. You might want to run an oil analysis to see what your viscosity is running when you drain it. Welcome to the boards.
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quote:

Originally posted by palmerwmd:
When I owned a VR6 engined VW it recommended 15w-40 in winter and 20w-50 in summer (1995)
I think the winter recommendation is now 5w-40 ( dont know if the sumemr recommendation changed as well).

Why are you running thinner oils?

Fred..
smile.gif


I think 5w-40 is what it VW recommends now-- but I imagine this recommendation is for dino oil. I'm running the Mobil because it is readily available, and I thicken up the 10w-30 with 15w-50 so I'm sure it is slightly thicker than straight 10w-30. I might switch to Redline or Amsoil, but I will probably lurk here for a little while before I decide.
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quote:

Originally posted by Bobert:

Anyways, what specs should I be looking for to determine if an oil is close to a 40wt? And what is the upper and lower ranges of a 30wt and 40wt. oils?


When you see the technical data sheet on an oil, look at it's viscosity at 100c. The range for 30wt is 9.3cst to 12.5cst and the range for 40wt is 12.5cst to 16.3cst.

So if you see an oil that's in the 11.5 to 12.5 range, that is considered an upper 30wt oil.
 
I would suggest using an ACEA A3/B3 rated motor oil. One benifit of the ACEA A3 rating is a high temperature high shear viscosity (HT/HS) of >3.5. From the ACEA web site: A3 Stable, stay-in-grade oil intended for use in high performance gasoline engines and / or for extended drain intervals where specified by the engine manufacturer, and / or for year-round use of low viscosity oils, and/or for severe operating conditions as defined by the engine manufacturer.

The two xxW-30 oils that I can think of that will be fairly easy to find are Castrol Syntec 0W-30 (German red label) and BMW High Performance Synthetic Oil 5W-30. Both of these oils are nearly 12 cst at 100 C. The Castrol Syntec 0W-30 is usually about $5.00 at AutoZone and the BMW HP Syn Oil is usually about $4.00 at BMW dealers. Both oils provide low wear numbers. The only negatives that I have heard about the BMW HP Syn oil is that it sometimes leaves a brown deposit on the inside of the oil fill cap. I think most complaints about this are due to BMW's VERY long oil change intervals of 10,000 miles or even 15,000 miles or two years whichever comes first for the newest BMW's. Also if you are willing to try a 40 wt oil AutoZone carries Mobil 1 0W-40. I don't know if you have Checker Auto Parts where you live but they sell Valvoline Synpower 5W-40 which is a very good oil. Also Amsoil 5W-30 would be an excelent choice in my opinion

[ October 20, 2003, 10:15 PM: Message edited by: Sin City ]
 
quote:

Originally posted by Bobert:
The thinner oil will lower the temps, but only about 10F lower--which is still pretty high
smile.gif
. The VR6 is a VERY hot running engine, no doubt about it. I've always felt the VR6 is a canidate for a slightly thicker grade than a 30wt because of the high temps.

Anyways, what specs should I be looking for to determine if an oil is close to a 40wt? And what is the upper and lower ranges of a 30wt and 40wt. oils?


Sounds like it would be a good candidate for an external oil cooler. IMO oil temp under reasonable loads should be within 20 degrees F of the water temp. I doubt the thing is running 225 degree F water temps...
 
quote:

Originally posted by jsharp:
Sounds like it would be a good candidate for an external oil cooler. IMO oil temp under reasonable loads should be within 20 degrees F of the water temp. I doubt the thing is running 225 degree F water temps...

I kinda have to agree about why VW did not install an oil cooler. The Corrado runs even hotter in the summer from what I've seen on vwvortex.com --like 260F. Some people install low temp thermostats to cool it down to a more reasonable temp. My coolant is due for a flush n' fill, so hopefully it should lower temps a little. I might try a little Redline Waterwetter when I flush too.

[ October 20, 2003, 10:41 PM: Message edited by: Bobert ]
 
You M1 mix is a good idea, but why toil with a lesser oil? Get the Delvac 1, if you can. The esters will transfers heat well. Wal*Mart's Rotella T Syn 5w-40 is a great choice for $3 a quart. I use GC otherwise. Check USA Syntec 10w-40, ACEA A3 and it is $3.75.
 
Delvac 1 has been on my list for quite a while now. I called up Mobil about 2 years ago to verify whether it was suitable for gasoline engines, which they confirmed. The only reason I never switched to Delvac 1 was because I bought so many 5 quart jugs of Mobil 1 at Walmart one day when it was on sale
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. I think they were clearing it out for the new Trisyn
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. I know Delvac 1 is available at various truck stops, so it shouldn't be too hard to find. Supposedly CAT has a rebranded Delvac 1 also.

Another Mobil 1 product I've been considering is 5w-40 (not the S brand for diesels). Supposedly (select?) Subaru dealerships carry this elusive grade which is mainly available in Europe.

I've been a little hesitant about using 0w-xx grades --it always seemed like I had to live in the Arctic to qualify for such a low viscosity. Is there anything to worry about using 0 grade in a hot climate?

As an aside, I've seen some information that Delvac could be bad for the catalytic converter in gasoline engines, but I assume this is misinformation. Maybe someone can clear that up
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.

Also I wanted to ask, what is Delvac 1 SHC?

http://www.exxonmobil.com/UK-English/Marine/PDS/GLXXENMRNEMMobilDelvac1_SHC5W40.asp
 
quote:

I've been a little hesitant about using 0w-xx grades --it always seemed like I had to live in the Arctic to qualify for such a low viscosity. Is there anything to worry about using 0 grade in a hot climate?

There's nothing to worry about whatsoever. With a good 0w30 like Amsoil or German Castrol Syntec, they maintain their viscosity very well, and are thicker than most 5w30s and 10w30s at operating temperature. I started running GC 0w30 in my car in August and it saw a lot of hot days, and my oil analysis came back looking very good.
 
Bobert,

Another option is to add about 50 mL per quart of Schaeffer's #132 to thicken up the M1 you already have on hand. #132 also adds an antimony AW/antioxidant to the oil and has Friction Reducers.
 
quote:

Another Mobil 1 product I've been considering is 5w-40 (not the S brand for diesels). Supposedly (select?) Subaru dealerships carry this elusive grade which is mainly available in Europe.

Has anyone been able to confirm if Mobil 1 5w-40 can be found at Subaru dealers? I called two in my area and none of them had it.
dunno.gif
 
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