5W-20 or 5W-30?

[tohi2009]

I'm not sure if someone already posted this question but my 2009 3.5 v6 engine#2GR-F2 and oil cap say 5W-20 but the dealer keeps putting 5W-30. So I took it back and told them to change it. They charge $29 bucks for oil change which is about the cost of the parts it I were to do it myself. My question to you pro's is, is it ok to put 5W-30 when my oil cap says 5w-20. I live in southern CA and it is hot. The coldest temp it get is about 55 degree in cold winter. I wouldn't call it winter compared to the east coast.No long distance driving but aloooot of stop and go traffic. Any advice will be great. Thanks.

[PhatRoyale]

The difference is really negligible at best.

Don't worry too much about it.

[humanoid]

The difference is so minor it should not make much of a difference. If it makes you sleep better at night then please insist that the dealer put in the correct weight of oil the next time you have your oil changed. Or, you can find another dealer or even DIY.

[nov0798]

Just get the cap that says 5-30

[Thunderchief]

I never trusted the viscosity on 5-20W but that is just me. I think 5-20W is great if you live in the arctic circle.

[summerwind]

Ah the religion of oil.

Multi viscosity oils work like this: Polymers (Viscosity Index Improvers) are added to a light base (5, 10, 20), which prevent the oil from thinning as much as it warms up.
At cold temperatures the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would.
The result is that at 100 degrees C the oil has thinned only as much as the higher viscosity number indicates.
Another way of looking at multi-vis oils is to think of a 5W-30 as 5 weight oil that will not thin more than a 30 weight would when hot.

In summary, 5W-30 is made from a 5 viscosity number stock and has Viscosity Index Improvers (VII) added to flow like a 30 viscosity number at 100 degrees C. 5W-20 starts out with the same 5 viscosity number stock and has Viscosity Index Improvers added to flow like a 20 viscosity stock at 100 degrees C.

Link to All about Oil.

All About Oil

May the force be with you

[zero4zero4zero4]

I remember reading somewhere saying that 5w-30 is actually better for your engine, however, auto manufacturers use 5w-20 as it provides better fuel economy.

[humanoid]

Originally Posted by zero4zero4zero4

I remember reading somewhere saying that 5w-30 is actually better for your engine, however, auto manufacturers use 5w-20 as it provides better fuel economy.

Do you remember better in what aspect?

[tohi2009]

Thanks for the replies . I guess I over reacted if there are hardly any difference. I just tried to follow the oil cap and owners manual recommandations to keep my car running top shape. Another thing I noticed was that dealer claim all toyota parts but when they do my oil change they use chevron or mobile oil instead of toyota formulated oil.

[summerwind]

In my area all dealers use Castrol SynBlend.
Toyota does not make their brand of oil. The QuikLub bays buy oil in 50 gallon drums and have a hose dispensing system.

As long as the oil meets there published spec you are ok.

[zero4zero4zero4]

Originally Posted by humanoid

Do you remember better in what aspect?

I think it was that in the long run, 5w-30 will provide better protection for the engine and in comparison, in the long run 5w-20 will have more engine wear. It is just that when auto manufacturers test for fuel economy, 5w-20 yield better results.

[bamlin54]

Use 5w20 unless you have the towing package, if you do use 5w30. Automotive engineers recommend viscosity's for a reason.

[lucky777]

Originally Posted by zero4zero4zero4

I think it was that in the long run, 5w-30 will provide better protection for the engine and in comparison, in the long run 5w-20 will have more engine wear. It is just that when auto manufacturers test for fuel economy, 5w-20 yield better results.

Is it a fact or pure speculation?

[bamlin54]

Automotive engineers test engines under various conditions for extended periods of time to arrive at a recommended oil viscosity. I have yet to see an automobile manual that says use whatever weight oil you want. Specific engines require specific oil viscosity under certain circumstances such as climate and use, which are outlined in the owners manual. I only use the recommended oil viscosity, have put hundreds of thousands of miles on several cars without an oil related failure. Just my 2 cents but I use Mobil 1 5w20 and will continue to do so. I would rather use 5w30 as it is much easier to find but I will stick with what the experts recommend.

[deadrx7conv]

Experts? If they were experts, we wouldn't be buried with recalls and TSBs.

Allaboutoil isn't all that great of a reference and pretty much misinformation as oils can be blended without VII's or VM's to meet many different weights. And, their 'summary' is wrong.

I have the tow package but I don't tow. So, why haven't the experts at Toyota addressed this? What if you tow without the tow package? They're experts with no common sense as they left out too many scenarios.

You can use just about ANY GF-4 or newer oil. Use a little common sense with weight. Don't use a 40 or 50 if you live at the north pole. And, I definitely wouldn't use a 20 weight pulling a 2-ton trailer in a desert.

I've used 0w20, 0w30, 5w20, 5w30, 10w30, 0w40... in my Highlander and various other vehicles with so-called 'carved in concrete' oil recommendations, and barely noticed any MPG differences(why oil went thin to begin with). The engine is also a little quieter with thicker oil.

If you're towing or live in a overly hot climate, I'd stick with the 0w40 or 5w40 as the average oil temperature is hotter. Since my vehicle is parked outdoors, I prefer the 0w20 or 0w30 for winter cold starts and 0w40 or 10w30 during the summer.

And, if you truly worry about your oil weight or brand, simply send out a used oil sample for analysis.

Tohi2009, what I would do is find out what brand/bulk oil they're using and its spec. If its garbage oil, whether its a 20 or 30 weight is meaningless. Its time that you find an independent to do your oil changes. Stick with name brand oil with the lastest API/SAE/ILSAC specs. ILSAC GF-5 is around the corner with most quality oils already meeting the GF-4 specs for a while. I've seen plenty of bulk/barrel oil at dealers with only an obsolete GF-3 rating(especially the 5w30 bulk). I would rather use a GF-4 5w20 over a GF-3 5w30 regardless of the owners manual's recommendation.
When in doubt, use a full synthetic which most dealers offer.

The new GF5 oils are already available and should be trickling into your local department and auto part stores over the next year.
http://www.gf-5.com/the_story/performance/