Grades for high ambient temperature locations

[GC617289]

Living in the greater Phoenix, Arizona area we have winter temperatures down to -4C/25F and summer temperatures above 43C/110F. There are days when it gets above 46C/115F.

I'm convinced manufacturer's recommended grades of 5W20 or 5W30 are not appropriate at higher ambient temperatures. I suspect that 10W40 or 10W50 is appropriate.

I'm a long, long time Mobil 1 user but the only oil that fits that spec is a high mileage formulation ... in the US. In Europe, however, they produce a 10W60 for BMW-M cars!

I know Mobil 1 is available in 0W40 but the 0W winter rating is overkill in the desert.

Comments on this are appreciated ...

 

[Quattro Pete]

Originally Posted By: GC617289
I'm convinced manufacturer's recommended grades of 5W20 or 5W30 are not appropriate at higher ambient temperatures.

Care to elaborate what makes you convinced of this?

Hint: just because you feel hot, doesn't mean that your engine does.

 

[GhostFlame]

Maybe Castrol Syntec 5w-50 available at NAPA stores.

Any 5w-40

You may someday drive to the mountains and it could drop to -5 F, that 5w would be a reasurring thing to me. And you have the 40 or 50 for better heat disbursement

 

[dparm]

Any off the shelf oil is totally fine. M1 0w40 is still a good oil even if you don't care that it's rated for low temps.

Only people who have to worry about ambient temps are cars making copious horsepower driven hard in Death Valley 18 hours a day.

I've yet to see a manufacturer say "if you live in the following states, you must run this oil". Tons of cars are sold in AZ, NM, TX, etc. and run for a long time on 5w20. See all those Civics and CR-Vs? 5w20.

 

[Chris142]

Just because it's 115F does not mean that your engine is running that much hotter to require a thicker oil. Almost All engines run somewhere between 180F and 230F depending on load. If they get Much hotter than 230F they will blow head gaskets and warp heads.

 

[Astro14]

Do you have an Oil Temp gauge? If it ran significantly higher in summer, then I would agree, you need a higher viscosity.

But I found that even in the Virginia Summer with sweltering humidity, the oil temp on my turbo Volvo, with the AC cranked, was about the same in the summer (95 C) as in the winter (90 C).

It only rose above 95 if I was towing or really driving hard.

so, summer heat didn't drive up the temp...manner of use did...

 

[HTSS_TR]

Manufactures test their cars/SUV's in Death Valley in Summer and International Fall in Minnesota in winter. If their engines can survive these two test locations with recommended oil grade, it is good anywhere else in North America, except may be Alaska or northern Canada.

 

[CATERHAM]

First welcome to BITOG.

If a 20wt oil is spec'd for an engine that is all that is necessary even on the hottest days in Arizona. The only thing that can really increase the viscosity requirement would be some extra ordinary use like towing a very heavy trailer in the mountains etc.
But for normal use their is no need to to deviate from the manufacturer's specified motor oil.

M1 0W-40 is an excellent light 40wt oil. As far as 0W-XX oils go it's one of the heaviest available judging by it's relatively high MRV viscosity spec' but that isn't what you should be looking at in terms of it's performance in your climate.
The main advantage of the grade is it's high viscosity index of 185. This means it's quite light on initial start-up even at room temperature while providing the high temperature protection of a 40wt oil.

 

[GhostFlame]

Originally Posted By: Astro14
Do you have an Oil Temp gauge? If it ran significantly higher in summer, then I would agree, you need a higher viscosity.
...(95 C) as in the winter (90 C).
It only rose above 95 if I was towing or really driving hard.


I have been wondering for awhile. in the old day pre 1985 cars had temp gauges that showed the numeral of the temp and normal was 210 to 235ish. Back then we could handle the facts. now with idiot lights or gauges that only show blue then red to indicate hot I've lost touch with my engine. my question, is the above temp range still about normal oprating temp for a gas engine?

 

[CATERHAM]

Actually most engine won't even see oil temp's of 212F.
Normal is a broad range from 180F to 235F or so.

 

[unixguru]

I don't think you should be concerned with 0w40. It's still one of the best oils in the world in my opinion. Mobil's HM oils are also very good. If you don't feel comfortable running regular 5w-20/30, then your engine should be just as fine with 0w40, HM version 5/10W-30, or even M1 HM 10w40. I wouldn't personally use 10w40 in a car which calls for 5w20, but have known people who did that without any issues. I think that going 1 grade above recommended wouldn't hurt anything except maybe fuel economy. I, myself, run 0w40 in the engine which calls for 5w30, and currently running 5w30 instead of recommended 5w20 in my other car. Haven't had any issues whatsoever.

 

[oldmaninsc]

Originally Posted By: HTSS_TR
Manufactures test their cars/SUV's in Death Valley in Summer and International Fall in Minnesota in winter. If their engines can survive these two test locations with recommended oil grade, it is good anywhere else in North America, except may be Alaska or northern Canada.

+1 I have a close friend who lives in Phoenix, Az. I am always amused that he (and others) think the heat in Arizona is somehow HOTTER than any place else in the nation.
My father used to live in Thermal, Ca (which isn't far from Palm Springs/Indio area) - their daytime temps. often exceed Phoenix and any other Az city by as much as 5 - 8 degrees (F.).

I've driven both vehicles at 80 - 85 going uphill with the a/c running full of blast and the outside temp. was 115 - 120F. Often the Chevy would have 4 adults and about 300 pounds of luggage and tools with both the front and rear a/c units running. Haven't had an engine failure yet - or even any weird noises or an increase in oil consumption.

I use 5W-20 in the Mercury all year long, including my 3 - 4 trips a year to Phoenix and I used 5W-30 in the Chevy.

Edit: That being said - IF it makes you sleep better at night - go ahead and use a XX - 40 oil.

 

[subiedriver]

I would just run the 0w-40 year round, it can definitely stand up to high heat, its a very stout oil.

 

[Astro14]

Originally Posted By: GhostFlame
Originally Posted By: Astro14
Do you have an Oil Temp gauge? If it ran significantly higher in summer, then I would agree, you need a higher viscosity.
...(95 C) as in the winter (90 C).
It only rose above 95 if I was towing or really driving hard.


I have been wondering for awhile. in the old day pre 1985 cars had temp gauges that showed the numeral of the temp and normal was 210 to 235ish. Back then we could handle the facts. now with idiot lights or gauges that only show blue then red to indicate hot I've lost touch with my engine. my question, is the above temp range still about normal oprating temp for a gas engine?


The engine temp wasn't marked on that model Volvo (1985 240 Turbo) but the oil temp gauge, which had the sender in the sump, showed that as a range. So, I can't really compare oil to water temp. The factory oil cooler was separate from the radiator, and had a thermostat in it as well, IIRC.

It would take a while to get up to temp when cold, but it ran 85-95, even when I had the car in Colorado. On a very cold day in Vermont, it would take a long, long time to get up to temp...but it still ran above 75-80, and that's with a -20 outside temp.

The more significant point is more that the oil wouldn't get too hot, even with the heat, humidity and AC load of summer driving.

I wish all cars were instrumented better...

 

[steve20]

the digital oil temps in my cars will run 207 in the winter to 230 in the summer. I maxed out at 235 on summer day. Average is 212. When it's 20 degrees out, it takes about 20 minutes of driving (non-highway) to get it up to even 198 degrees



Steve

 

[bluesubie]

Originally Posted By: Quattro Pete
Originally Posted By: GC617289
I'm convinced manufacturer's recommended grades of 5W20 or 5W30 are not appropriate at higher ambient temperatures.

Care to elaborate what makes you convinced of this?


As dated as it may be, it's actually stated in the Subaru owner's manual.
Quote:
Engine oil viscosity affects fuel economy. Oils of lower viscosity provide better fuel economy. However, in hot weather, oil of a higher viscosity is required to properly lubricate the engine. ...

If the vehicle is used in desert areas, in areas with very high tempuratures, or used for heavy duty applications such as towing a trailer, use of oil with the following grade and viscosities is recommended:
SAE Viscosity No. 30, 40, 10W-50, 20W-40, 20W-50.


-Dennis

 

[dparm]

BTW I had my high-revving Acura Integra GS-R at Firebird years ago (while I was in school) and never had a single overheating problem or oil consumption problem. And that was on M1 5w20!

Compression was perfect and the car burned no oil when I sold it at 80k.

 

[chubbs1]

Originally Posted By: steve20
the digital oil temps in my cars will run 207 in the winter to 230 in the summer. I maxed out at 235 on summer day. Average is 212. When it's 20 degrees out, it takes about 20 minutes of driving (non-highway) to get it up to even 198 degrees



Steve

+1 this is the problem with using thick oils in vehicles not spec'd for them. Your engine doesn't run much if any hotter in the summer as it does in winter, and the thicker oil takes longer to get up to temp, so if you short trip it can pose a problem for you. Just use what your engine specs say. Also thinner oil dissipates heat quicker than thick oil.

 

[jorton]

My cars are noticably warm natured. On cool winter mornings they're buzzy and rough idling during warm up and they take a long time to warm up. Ran 5w-20 and 5w-30. After the oil thins they run smoother.

So they're seasoned for warm climate operation. With that said, what would you do with the summer oc for the car that ran 5w-20 over the winter? She ran 5w-30 last summer.

Where are you GC617289?

 

[antonmnster]

On a hot day around here, the A6's oil will pretty easily get up to 230F when on the interstate. Of course the coolant temp is maintained. I could see extreme ambient temps being a legitimate cause for concern.