Thicker oil, summer-thinner oil, winter

[Mystic]

I don't know about the rest of you guys, but driving around Colorado, New Mexico, Arizona, Utah, etc., with 5W-30 and 10W-30 oils in the summertime makes me nervous. Maybe I am just old fashioned, but when you drive in Arizona and the temperature is 115 degrees you feel like you need 15W-40 in the engine. But the owner's manual says 0W-30, 5W-30. 10W-30, or else. With my current Saturn, you can't even use a straight 30 wt. I don't think much of Western Europe experiences Arizona temperatures, but they seem to be able to use thicker oil when the need arises.

Now don't get me wrong-5W-30 is fine in the wintertime. Heck, 0W-30 in Minnesota.

Maybe the answer is synthetics, I don't know.

 

[G-MAN]

quote:

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Originally posted by Mystic:
Maybe the answer is synthetics, I don't know.

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Now you're talkin'!! Fill that baby up with a good 0w30 or 0w40 synthetic and run the snot out of it—no matter what the temp.

 

[mirou]

I think with the Schaeffer's oil you just bought, you don't have to worry. micron moly 5W30 is made from group II+ basestocks and obviously has some **** good additives and chemistry. For peace of mind you could just get supreme blend 10W30. the film strength of that would be real high I would think.

 

[Schmoe]

Won't worry about it, bro. Been running the 10W-30's for years in the Oklahoma and Texas heat, that includes long periods of idle, and all is still good. If you didn't change at 3K, say you went a little further, I at least do that and don't sweat it.

 

[Starbreaker666]

Whats up Mystic. I live out in Limon and I have used 10w-30 all my driving life with 0 problems even in the cold eastern plains ground blizzards. Ollny time I got nervous is when the snow was so deep i had to drive my old 83 Blazer modified for rock crawling. it was -10 and made a **** of a racket a couple seconds after i started it. went away a few seconds later. no probs with it at all now...

 

[mph]

When it's cold out, my coolant temperature gauge is steady at one tick below the middle (after the car warms up). When it's 115 F out, the gauge is in exactly the same place. And my radiator is only half-width, and I drive hard.

Now, I don't have an oil temperature gauge, so maybe I'm off base, but based on the coolant I don't see why my oil should care about the outside temperature. The cooling system seems to do its job of regulating engine temperature. If I had an aircooled car, I'd probably see things differently.

 

[moribundman]

My manual (for my '96 Audi A4) strongly discourages the use of SAE 5W-30 oil, if the ambient temp is above 55 degr F. If I use synthetic oil, then 5W-30 is fine. So yes, I wouldn't use a 5W-30 dino oil at high temps.

 

[moribundman]

/\/\ /\/\

My previous post was a reply to Mystic's original post. I'd also like to add that Europe can get very hot. Even Germany has days with over 100 degr. F, and Greece and Italy can get really hot. As for the thicker weight oil that people use there:
Don't forget people redline their cars for hours there. I doubt you'll do that here.

5W-40 is a popular weight for many European cars.

 

[MNgopher]

My old '89 cavalier did just fine on dino 5w30 oils when I lived in Colorado with frequent trips to Utah and Arizona.

Imagine the engine (2.0 OHV 4cyl - all 96 hp)dropping into 2nd gear (3-speed tranny) on a long mountain pass at 95+ degress. Don't ask the RPMS - you don't want to know.

Drove her to 163000 miles before I sold it. Ran fine.

Always on 5w30 dino.

 

[Quick_lude]

quote:

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Originally posted by MNgopher:
Imagine the engine (2.0 OHV 4cyl - all 96 hp)dropping into 2nd gear (3-speed tranny) on a long mountain pass at 95+ degress. Don't ask the RPMS - you don't want to know.

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Hmm.. let me guess.. 4,000 rpm?

I would use 10w30 synthetic myself.. Maybe M1 0w40 and **** the manual..

 

[MikeW]

One, I think alot more depends on the cooling system in these situations. If it can keep the engine running in it's normal temperature range, then you shouldn't have to up your viscosity in the summer.

This is also a situation where synth vs dead dino also becomes an issue. Dead dino starts out as a straight base oil at the winter weight (say 5W) and then they add VII to get it to act as a straight 30 at 100C. If the VII has sheared down under stress, your 5W30 may not be a 30 any more. This would be bad in a high temp situation. A good (real PAO/Ester based) synth should be inherently 5W30 without VII. It won't shear down, and should maintain it's viscosity. So if they oil stays at the right weight, and the cooling system keeps the engine temp in range, you shouldn't have any problems with a 'normal' vis oil in high ambient temp situations.

 

[kiko]

I'll be going to Phoenix on Friday. The german syntec's already in the engine. We'll see if it can handle the Arizona heat. I would think so. Keep you posted!

 

[porterdog]

quote:

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Originally posted by mph:
When it's cold out, my coolant temperature gauge is steady at one tick below the middle (after the car warms up). When it's 115 F out, the gauge is in exactly the same place. And my radiator is only half-width, and I drive hard.

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I don't know what you drive, but on one of my cars the mfg dumbed down the gauge to keep people from worrying. From about 180F-230F the temp needle doesn't move. Sucks, but it's by design.

$0.02,
Robert

 

[Dr. T]

For those of you with U.S. cars that don't spec. thicker oils (due to CAFE), I think the primary decision to go thicker should be based on excessive consumption. If engine is in good condition, there should be little to no consumption...ie. 1qt/1k mi. or even 3k shouldn't really be considered as normal. Any more and be forwarned that your engine is running hotter than the oil can take and some will burn out the pipe, the rest will cook/coat and sludge up the inside of the engine. The second reason is as far as I can see it...thicker oils can do longer intervals as a general rule of thumb. Unless you're using the newer LongLife synthetics eg. German Syntec 0-30...but then rule 1 applies and overrides this rule 2.

 

[Sin City]

I agree with Dr.T. I don't think that a car that is in good condition should need a lot of oil added. If your car is running on 5W-20 and not using (burning) oil and you are changing it often than just keep using the thin oil until you need to add oil often. In the three cars I own I don't have to add any oil in 4,000 to 5,000 miles of driving and if I did I would surely use a thicker oil so that I could stop adding oil in between oil changes.

[ July 02, 2003, 08:10 PM: Message edited by: Sin City ]

 

[Drew99GT]

I feel your pain Mystic, I'm up in the Springs. After heading up Highway 24 west of CO Springs when it's 95 outside, the oil pressure on my Dad's 98 4.3L Blazer DROPS when you come to the stoplights on the pass (elevation gain of over 3,500 feet in a very short distance). So I put in some penz 15w-40 and it totally helped the oil pressure, and power. I think it provides better ring seal because it does have 130K of hard mountain driving. With engines under 100K, I'd say 10w-30 is totally fine here in sumertime CO. You also have to factor in the possibility of below 30 degree weather at night in the mountains to, so 10w-30 is a good compramise. **** , two weekends ago, it got to about 35 degrees out west of Fairplay CO at night when I went camping.