5w30 vs 20w50 for short commutes?

[ScoobySTi07]

What are the drawbacks/benefits of using the recommended 5w30 vs 20w50?

These are the specifics of the car in question.
1. Vehicle: Subaru STi (ie 2.5L turbo)
2. Manual suggested: SAE 30 to 20w50 under "severe conditions"
3. Where you live: Mobile, AL
4. How you drive: Fast
5. What your daily drive is like: 7 min daily city commute
6. Whether your car has any known problems: N/A

I'm looking into this for a friend. Alabama can get warm but 50 seems like a lot for anything other than track applications given a mostly stock engine though I've been wrong before.

 

[dgunay]

I'd try 10w30, PP or Mobil 1

 

[jk_636]

If the manual said the motor can handle it then go for it. Alabama gets plenty warm during the summer months (that aren't that far away) and it should run just fine. Gas mileage may take a little hit, but if your friend drives fast, chances are he is not worried about gas mileage. Just my

 

[Bandito440]

I don't think I'd use either one. Rotella T6 is the preferred oil for these engines, and I can't think of a good reason to use anything else.

 

[147_Grain]

Mobil 1 0W-40 due to your "fast" driving style in a warm climate like Alabama and fuel dilution from short trips.

Mobil in Mobile is easy to remember.

Follow the Severe Maintenance Schedule while under warranty.

 

[toneydoc]

I like 147 Grains advice. He gave a good recommendation

 

[demarpaint]

Originally Posted By: toneydoc
I like 147 Grains advice. He gave a good recommendation


You can't beat M1 0W40.

 

[krismoriah72]

Your screen name is the same as your friends car...are you the co pilot? The question was 5W30 vs 20W50 for short commutes...the answer 5W30.

Since you only have a 7 minute commute and you drive really fast, i would save the money from expensive synthetic oil and put it towards a speeding ticket fund.

YMMV.

 

[aquariuscsm]

Thinnest I'd go would be a 10W40. Subaru's spec sounds like mine (10W30 for fuel economy,10W40-20W50 for extended high speeds and racing). But mine says not to use anything below 10W30 (it specifically warns not to use 5W20/5W30). If he wants an excellent cheap synth,there's Mobil 1 15W50.

 

[friendly_jacek]

7 min daily commute?
wrong car for that.

 

[Jimzz]

Yea try and 0w40 or 5w40. But a high mileage 5w30 would also work well I bet.

 

[KCJeep]

It sounds to me like they are trying to spec an oil with an HTHS of at least 3.5, the SAE 30 or any light 40 (0w40, 5w40 or 10w40) will meet that. A 5w30 will not.

The 5w30 would not be an issue for those extreme short trips but what is he supposed to do on the occasions he goes farther? Change the oil?

The Rotella 5w40 or Mobil 1 0w40 seem the best choices to me.

A HDEO 10w30 would also cut it, like Rotella T5, Valvoline synblend or Delo.

 

[camrydriver111]

According to Dr. Haas oil philosophy he should be using 0W20.

 

[Nick1994]

Originally Posted By: 147_Grain
Mobil 1 0W-40 due to your "fast" driving style in a warm climate like Alabama and fuel dilution from short trips.

Mobil in Mobile is easy to remember.

Follow the Severe Maintenance Schedule while under warranty.
+1

 

[riggaz]

5w-30 is the preferred viscosity for standard operation

5w-40 is a good recommended alternative along with many others like 10w-30/40/50

At 7 minutes all of your driving is done with the oil cold/cool and not at it's ideal operating temp

you would have to do some research to try and ascertain what the "severe conditions" are

I remember Shannow typing something about a thicker oil film giving more protection until the additive package switched on so might be worth a pm to him.

 

[Shannow]

Originally Posted By: camrydriver111
According to Dr. Haas oil philosophy he should be using 0W20.


But there's so many errors in 101, I wouldn't follow that philosophy unless I had a lot of spare cash to throw at a failure.

A3/B4 5w30 would be my advice.

 

[CT8]

Originally Posted By: Shannow
Originally Posted By: camrydriver111
According to Dr. Haas oil philosophy he should be using 0W20.


But there's so many errors in 101, I wouldn't follow that philosophy unless I had a lot of spare cash to throw at a failure.

A3/B4 5w30 would be my advice.
Yes but since it is on the internet the non discerning people blindly believe it.

 

[ScoobySTi07]

Thanks for all the responses. I look forward to more info and opinions on the recommended vs alternatives question. So far I'm getting a it's not bad, it's not great but there are better choices than 20w50.


Personally I run Rotella T6 5w40 in my '08 STi. It's a solid oil at a good price point for a synthetic. I've been testing out extended runs with it as 3750 miles per change appears to be a little excessive for a mostly mild 30 minute daily highway commute but that's a topic for a different time and thread.

 

[FutureDoc]

Don't thrash it until it is warm. Does not matter what the oil happens to be.

10w30, Xw40 HDEO would be my choice (heck, I use T5 in a NA Outback). I would not toss 20w50 into it (unless there is something different lurking with the vehicle).

 

[NH73]

Originally Posted By: KCJeep
It sounds to me like they are trying to spec an oil with an HTHS of at least 3.5, the SAE 30 or any light 40 (0w40, 5w40 or 10w40) will meet that. A 5w30 will not.

The 5w30 would not be an issue for those extreme short trips but what is he supposed to do on the occasions he goes farther? Change the oil?

The Rotella 5w40 or Mobil 1 0w40 seem the best choices to me.

A HDEO 10w30 would also cut it, like Rotella T5, Valvoline synblend or Delo.


If that is the case that the HTHS min. is 3.5, then they couldn't list 10w30 as acceptable.