Summer Oil Viscosity - 10w40? Good?

[SN95Audi87]

Hi All,

Right now I am using 5w40 Euro formula all year around in the tri-state area. I wanted to know is 10w40 good for 1.8T cars that see above average driving, we can call it "spirited" driving if you like...the temperatures are rising above 80* degrees outside and I am do for a oil change. What are your concerns for this type of oil? Do you think 10w40 is a great choice for the summer? Would this create more pressure in the engine and cause further problems down the road? Would you run this in high mileage engine for summer only? I would like to hear your thoughts.


Nathan

[Believer]

Both have the same warm viscosity of 40 therefore should provide similar if not the same heat protection. The differences are in their cold viscotities of 5 and 10, the former being thinner at startup. I'm not a oil wizard but my gut concern would be the 10s impact on startup protection.

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[SN95Audi87]

Both have the same warm viscosity of 40 therefore should provide similar if not the same heat protection. The differences are in their cold viscotities of 5 and 10, the former being thinner at startup. I'm not a oil wizard but my gut concern would be the 10s impact on startup protection.

Sent from my LG-H815 using Tapatalk

I agree! If its minimal between the two I will stick to 5w40, but I do like the added benefit of it being slightly more vicious since turbo cars generate a ton of heat especially in the summer. 75% of my driving is done the highway and I see oil temps at 190-210 range all the time. Sometimes it creeps up to 225-250 when I going up giant grade on a mountain where I live. The RPMS stay no less then 3k for about 2-4mins...

[richardodn]

VW/Audi recommends oils that meet their 502 00 spec for both the 1.8T and 2.8 liter motors. To properly handle the heat generated by the turbo, you'll want to use a full synthetic (to withstand heat without degrading) as well as the oversized oil filter (to reduce temperatures by increasing volume). Viscosity has nothing to do with heat protection. Either a 5w40 or 10w40 will be fine for summer provided these other criteria are met. Personally I use Mobil 1 0w40 Euro car formula which is available at Wal-Mart in 5 qt bottles for a great price.

[SN95Audi87]

VW/Audi recommends oils that meet their 502 00 spec for both the 1.8T and 2.8 liter motors. To properly handle the heat generated by the turbo, you'll want to use a full synthetic (to withstand heat without degrading) as well as the oversized oil filter (to reduce temperatures by increasing volume). Viscosity has nothing to do with heat protection. Either a 5w40 or 10w40 will be fine for summer provided these other criteria are met. Personally I use Mobil 1 0w40 Euro car formula which is available at Wal-Mart in 5 qt bottles for a great price.

I'm not really worried about heat protection since I've been using full synthetics since ownership which are w40. I'm worried about oil consumption and burn off from heat production of turbo/engine. I know for sure 0w40 weight will get eaten up quicker by the engine compared to 5w40 or 10w40. My concern is that will the 10w40 slow consumption down a bit since its slightly thicker and take more a beating. I guess they all have pros and cons. Lighter weight oil = faster spool, but more consumption. 10w40 = heavier weight, slower spool, possibly more drag on internals. All in all these characteristics are probably minimal at best.

[Thumper3]

As has been mentioned and touched on........the difference between 5-40 and 10-40 at operating temp is....nothing.

Here's something else to think about, the lower rating is based on how the oil flows at freezing.........so a 5-40 only flows at 5 when it's freezing, it is thicker when warmer (it's the magic of synthetics and additives, don't question it LOL).

This means that when ambient temp is say 80+ a 5-40 is not flowing at 5 when you start it up, it's more like a 10 anyway. But some places even in summer it can drop to lower temps overnight, you lose nothing by going with the 0 or 5 rating but gain that extra protection when truly cold out.

Take away, there's no real "summer" and "winter" difference with modern synthetics, and there's no real point to change to a 10-40 in the summer "because I don't need the cold protection". Now if the engine is worn out and you need thicker oil to control compression and blowby I could see using thicker stuff.....but that's an engine issue, not a season issue and you're pretty much stuck running that year round anyway.

Ultimately, it's the manufacturers specification first, and the viscosity at operating temp rating second that are most important, especially if you are smart and letting the engine idle for a couple minutes after startup just to give the oil time to circulate to every nook and cranny. The cold rated viscosity is only really vital if you live in frigid cold locations and then it's still about going lower to get that zero and below protection ability.

So running 5-x or 0-x in a hot climate instead of 10-x is not a real concern, but running 10-x in a brutal cold climate IS the thing to avoid.

[SN95Audi87]

As has been mentioned and touched on........the difference between 5-40 and 10-40 at operating temp is....nothing.

Here's something else to think about, the lower rating is based on how the oil flows at freezing.........so a 5-40 only flows at 5 when it's freezing, it is thicker when warmer (it's the magic of synthetics and additives, don't question it LOL).

This means that when ambient temp is say 80+ a 5-40 is not flowing at 5 when you start it up, it's more like a 10 anyway. But some places even in summer it can drop to lower temps overnight, you lose nothing by going with the 0 or 5 rating but gain that extra protection when truly cold out.

Take away, there's no real "summer" and "winter" difference with modern synthetics, and there's no real point to change to a 10-40 in the summer "because I don't need the cold protection". Now if the engine is worn out and you need thicker oil to control compression and blowby I could see using thicker stuff.....but that's an engine issue, not a season issue and you're pretty much stuck running that year round anyway.

Ultimately, it's the manufacturers specification first, and the viscosity at operating temp rating second that are most important, especially if you are smart and letting the engine idle for a couple minutes after startup just to give the oil time to circulate to every nook and cranny. The cold rated viscosity is only really vital if you live in frigid cold locations and then it's still about going lower to get that zero and below protection ability.

So running 5-x or 0-x in a hot climate instead of 10-x is not a real concern, but running 10-x in a brutal cold climate IS the thing to avoid.

Thanks for that solid chunk of information. In my other thread my OEM turbo partially went out so that is the reason for my oil burn. The car has 175k on it and doesn't smoke at all but more so eats it. I was running 0w40 for a few years then went to 5w40. If there is no real difference in the summer I will return back to 0w40 when I replace the turbo with a new one. Thanks for the clarification.