YACT: can i use 5w-30 instead of 0w-40

[Aharami]

just started using synthetic oil since last oil change and the car definately feels smoother. well the only place that sells 0w-40 oil around here is a local oil change place. i dont wanna pay $65 for an oil change but cant find any retailers selling 0w-40...the closest thing they have is 5w-30 or 10w-40.

can i use those instead of the 0w

also whats the difference between the three? which is best for the summer?

i used the 0w-40 last time cuz its says its made for european cars and i have a VW GTI

 

[mugs]

Just buy the 5W-30, use it, and return it when you're done. After all, you only wanted to use it for 3 months, why should you have to pay for it? If they charge you a restocking fee, demand to speak to a manager.

 

[Vette73]

5W30 will be just fine. Your owners manual probable sayd to use either 5w30 or 10w30. Check and see, but 5w30 (or even 10w30) will be juts fine.

 

[Eli]

0W-40 is much better for the summer.

Mobil1 SuperSyn 0W-40 is some pretty good stuff overall.

You can certainly use 5W-30, but I wouldn't, particularly if your engine has seen only 40 weight oil its whole life, or if you live in a very hot climate.

What kind of car?

There is quite a bit of difference. Mobil1's 0W-40, besides being thicker overall, has much better shear stability than Mobil1's 5W-30.

This means that the oil will not thin out as much with use.

That is the main difference spec wise. They both have similar flash points, TBN, etc.

The 0W-40 also has a much better viscosity index, which means it thins to proper viscosity quickly, which is a good thing.

 

[iamwiz82]

i used the 0w-40 last time cuz its says its made for european cars

Marketing Executives love people like you

 

[Eli]

Originally posted by: iamwiz82

i used the 0w-40 last time cuz its says its made for european cars

Marketing Executives love people like you

Heh.. Well, he speaks the truth.. but it isn't because the car itself is European..

It is because people in Europe have a much longer standard oil change interval. Thus, not only do they need a heavy-duty oil, they also need an oil that will work through a wide variety of temperature extremes - hence the 0W spec.

 

[ElFenix]

is valvoline maxlife just a marketing gimmick?

 

[Eli]

How long has the current oil been in use? I would recommend just going a little longer, or finding a place that stocks the 0W-40. Wal-Mart should have it.

Also, you must remember that your oil can only be as good as your filtration.

If your air and oil filters suck it quite simply doesen't matter which oil you use(although some are going to be better at fighting the contamination than others, the end result is the same - wear).

Depending on how you think, run a PureOne oil filter. Change at your normal intervals. They're about 6 bucks, and they filter nominally at 10 - 20 microns.

If you're going to do this, I say take it a step further and pre-order an AMSOil oil filter before each oil change. It filters 98% at 10 microns and 50% at 6 microns. This is exceptional. Your typical 3$ Fram might filter 50% at 20 microns and 98% at 40 microns.

They're about 10 - 12$, but they're 6 month, 12k mile filters. So you'll only have to buy one instead of 2 PureOne's.

If you don't want to bother with AMSOil, then Mobil1's filters are high quality, but still on the spendy side.

 

[Eli]

Originally posted by: ElFenix
is valvoline maxlife just a marketing gimmick?

10W-30 MaxLife is marginally better than their regular 10W-30.

Higher TBN(supposedly to deal with the extra combustion byproduct contamination that comes with engine wear), and a better flash point.

I guess if you're a Valvoline fanboy, thats a good thing.. lol.

Otherwise, there are perhaps a dozen conventional oils that are better. Valvoline's convetional oils are nearly bottom of the barrel, but their synthetics are top of the line(amongst the readily available brands) in almost all grades.

 

[ElFenix]

ok, whats the best conventional? or can i switch to mobil 1 at 25,000 miles?

 

[Eli]

Originally posted by: ElFenix
ok, whats the best conventional? or can i switch to mobil 1 at 25,000 miles?

I'm ignoring your edit.

You can certainly swith to synthetic at 25k. You can switch to synthetic at any milage in any newer automobile.

The best conventional 10W-30 is Mobil Delvac 1300 Super 10W-30.

The best synthetic 10W-30 is Havoline Synthetic or Valvoline SynPower.

The best conventional 5W-30 is Havoline Energy.

The best synthetic 5W-30 is Havoline Synthetic.

The best synthetic 0W-40 is Mobil1 SuperSyn. <-- I really recommend this oil, especially if you live in a hot climate)

The best conventional 10W-40 is 76 Lubricants Nascar HP.

The best synthetic 10W-40 is 76 Valvoline HP Syn or 76 Lubricants Nascar Synthetic.

Should I go on?

If you can use a 40 weight oil per your manuals suggestions, DO IT. Your MPG will be reduced very slightly. Less so if you use a synthetic. It won't be noticable.

Remember though, you would be better off to skimp and buy 1.25/quart conventional oil and pair it with a decent oil filter than the other way around.

Infact, buying expensive oil and then pairing it with a cheap ass oil filter is almost entirely pointless. Of course, buying good oil and a good oil filter will just be that much better.

 

[ElFenix]

ok that is a lot to remember

5W 30 preferred, can used 10W 40 if the temp is above some cold temp that has never been seen in texas

 

[Eli]

Originally posted by: ElFenix
ok that is a lot to remember

5W 30 preferred, can used 10W 40 if the temp is above some cold temp that has never been seen in texas

You live in Texas? Use 40 weight. Your engine will thank you.

0W-40 would be an excellent choice all year around.

It's viscosity at -35F(6200cP) is comparable to most conventional 10W-30 at -25F.

That's all the xW rating is. The oil has to score under a certain viscosity at a certain temperature. It has little to do with the actual viscosity of the oil. 5W-30, 10W-30 and straight 30 are all 30 weight oils, they just have different cold temperature properties.

Of course, you never see those temperatures in Texas, but it's still nice to know that on those bone-chilling 50 degree days, your oil is going to be just as fluid as ever.

lol..

 

[CFster]

Originally posted by: Eli

Originally posted by: ElFenix
ok, whats the best conventional? or can i switch to mobil 1 at 25,000 miles?

I'm ignoring your edit.

You can certainly swith to synthetic at 25k. You can switch to synthetic at any milage in any newer automobile.

The best conventional 10W-30 is Mobil Delvac 1300 Super 10W-30.

The best synthetic 10W-30 is Havoline Synthetic or Valvoline SynPower.

The best conventional 5W-30 is Havoline Energy.

The best synthetic 5W-30 is Havoline Synthetic.

The best synthetic 0W-40 is Mobil1 SuperSyn. <-- I really recommend this oil, especially if you live in a hot climate)

The best conventional 10W-40 is 76 Lubricants Nascar HP.

The best synthetic 10W-40 is 76 Valvoline HP Syn or 76 Lubricants Nascar Synthetic.

Should I go on?

If you can use a 40 weight oil per your manuals suggestions, DO IT. Your MPG will be reduced very slightly. Less so if you use a synthetic. It won't be noticable.

Remember though, you would be better off to skimp and buy 1.25/quart conventional oil and pair it with a decent oil filter than the other way around.

Infact, buying expensive oil and then pairing it with a cheap ass oil filter is almost entirely pointless. Of course, buying good oil and a good oil filter will just be that much better.

Where are you getting this information?

 

[Pepsi90919]

The best synthetic 10W-30 is Havoline Synthetic or Valvoline SynPower

wtf?

 

[Aharami]

Originally posted by: iamwiz82

i used the 0w-40 last time cuz its says its made for european cars

Marketing Executives love people like you

yea i love them too. i go about 6-8k between oil changes so i wanted to get the oil thats gonna "last the longest"

anywho....i ended up getting the 0w-40 at the oil change place. i guess i'll get the 0-40 from autozone next time and change my oil myself.

 

[OS]

Originally posted by: Eli

Originally posted by: ElFenix
ok that is a lot to remember

5W 30 preferred, can used 10W 40 if the temp is above some cold temp that has never been seen in texas

You live in Texas? Use 40 weight. Your engine will thank you.

0W-40 would be an excellent choice all year around.

It's viscosity at -35F(6200cP) is comparable to most conventional 10W-30 at -25F.

That's all the xW rating is. The oil has to score under a certain viscosity at a certain temperature. It has little to do with the actual viscosity of the oil. 5W-30, 10W-30 and straight 30 are all 30 weight oils, they just have different cold temperature properties.

Of course, you never see those temperatures in Texas, but it's still nice to know that on those bone-chilling 50 degree days, your oil is going to be just as fluid as ever.

He'll lose some power if he uses 40W though. If it were up to me, and the manual says it's ok, I'd just stick to any of the 30W.

 

[Eli]

Originally posted by: Pepsi90919

The best synthetic 10W-30 is Havoline Synthetic or Valvoline SynPower

wtf?

Why's that a wtf?

Valvoline SynPower 10W-30 is a top of the line oil, right below AMSOil, Neo and Red Line.

Originally posted by: OS

He'll lose some power if he uses 40W though. If it were up to me, and the manual says it's ok, I'd just stick to any of the 30W.

It will be very, very slight, if anything.. especially with synthetic.

The difference between 30 and 40 weight oil is only ~3cP @ 100ºC, but the potential spec benefits are worth it. And if he's been using conventional 5W-30, I bet there will be very little if any difference with a synthetic 0W-40, since it will have a better anti-friction package, if it's a higher end synthetic.

If he were to be interested in running 20W-50, there may be more concern about fuel economy and power.

But yeah. It's entirely too easy to focus WAY too much on the oil. Like I said, it would be better to focus on filtration and get just about any cheapass oil you want. They're all API certified, they all meet minimum specs deemed safe. Some just go above and beyond the call of duty.

 

[OS]

Originally posted by: Eli
It will be very, very slight, if anything.. especially with synthetic.

The difference between 30 and 40 weight oil is only ~3cP @ 100ºC, but the potential spec benefits are worth it. And if he's been using conventional 5W-30, I bet there will be very little if any difference with a synthetic 0W-40, since it will have a better anti-friction package, if it's a higher end synthetic.

If he were to be interested in running 20W-50, there may be more concern about fuel economy and power.

But yeah. It's entirely too easy to focus WAY too much on the oil. Like I said, it would be better to focus on filtration and get just about any cheapass oil you want. They're all API certified, they all meet minimum specs deemed safe. Some just go above and beyond the call of duty.

Well, it's not fair to make comparisons across two oils with different weights and types. To be fair, you must compare either the two types, or two different weights.

An additional consideration is that I think elfenix has a QR25 based SER. It's a big 4 cylinder with a long ass stroke. Due to it's long stroke, piston speeds are high, making it more sensitive to power losses due to internal friction. Hondata/HAsport has documented this phenomenon in Honda's K24, a similar engine in terms of bore/stroke and displacement. On built K24s, as revs build, the TQ falls off because internal friction kills power. It would stand to reason that a thinner/better oil would reduce frictional losses.

I think he should use Mobil 1 in the lightest weight appropriate for the region he is in as specified by the manual.

 

[Eli]

Originally posted by: OS

Originally posted by: Eli
It will be very, very slight, if anything.. especially with synthetic.

The difference between 30 and 40 weight oil is only ~3cP @ 100ºC, but the potential spec benefits are worth it. And if he's been using conventional 5W-30, I bet there will be very little if any difference with a synthetic 0W-40, since it will have a better anti-friction package, if it's a higher end synthetic.

If he were to be interested in running 20W-50, there may be more concern about fuel economy and power.

But yeah. It's entirely too easy to focus WAY too much on the oil. Like I said, it would be better to focus on filtration and get just about any cheapass oil you want. They're all API certified, they all meet minimum specs deemed safe. Some just go above and beyond the call of duty.

Well, it's not fair to make comparisons across two oils with different weights and types. To be fair, you must compare either the two types, or two different weights.

An additional consideration is that I think elfenix has a QR25 based SER. It's a big 4 cylinder with a long ass stroke. Due to it's long stroke, piston speeds are high, making it more sensitive to power losses due to internal friction. Hondata/HAsport has documented this phenomenon in Honda's K24, a similar engine in terms of bore/stroke and displacement. On built K24s, as revs build, the TQ falls off because internal friction kills power. It would stand to reason that a thinner/better oil would reduce frictional losses.

I think he should use Mobil 1 in the lightest weight appropriate for the region he is in as specified by the manual.

Interesting. Makes sense. And Yes, I agree. You really shouldn't compare oils of different weights.

As for the manual, I also agree.. to an extent. If it says he can use a 10W-40in the temperature range he'll be in, then he can certainly use it.. like you said, with the aforementioned loss of power. But I really stress that it is going to be pretty insinificant, unless he dynos his car every week. Especially if he's been using a conventional oil.

It was just that in my opinion, the extra protection would be worth it, especially in the Texas summer.

Our Camry can use 20W-50 if the temp is above 50 degrees. It's getting either Castrol Syntec 5W-50 or 76 Lubricants Nascar Synthetic 20W-50 next oil change, since it's summer. The 5W-50 is an interesting proespect since it flows so well in the cooler temps.

IMO, if you care about longevity, use the recommended grade in the middle, especially if you drive in extreme conditions.

 

[rufruf44]

What do you think about the shift toward 5W-20? I know Honda is recommending that in their manual, and some owner at BTOG reported good result, but I'm still iffy running that in the middle of the summer heat.

 

[Eli]

Originally posted by: rufruf44
What do you think about the shift toward 5W-20? I know Honda is recommending that in their manual, and some owner at BTOG reported good result, but I'm still iffy running that in the middle of the summer heat.

Really, people are reporting "good" results with it?

What is considered "good"?

While it's true that the oil probably protects adequately, it is a gimmick to get better CAFE stats.

You have to remember that the manufacturer could care less if their engine lasts 250,000 miles. By that time the car is long out of warranty etc. They don't have your best interests in mind when they write the manual.

20 weight oil has an even worse shear stability minimum spec than 30 weight, 2.60 vs. 2.90. :Q Not to mention it's a lighter oil.

I wouldn't use it if you care about longevity.

If you insist, Pennzoil 5W-20 is the best conventional and Mobil1 SuperSyn is the best 0W-20 synthetic.