Use thicker oil for my summer only car?

[wowthisexists]

To review, you want a low viscosity in the cold, right? Is the following idea correct?
For a winter only car, you might want 10W-50 instead of 20W-50 for better cold start viscosity.
For a summer only car, you might want 20W-60 instead of 20W-50 for better extreme summer protection.


My weekend car is supposed to use 20W-50.
But, I basically never drive it when it's under 30 degrees out.
Since I store it all winter, what oil weight could I use for better summer protection?

 

[Astro14]

It really depends on your oil temperature, not the outside air temperature.

Depending on the car, there may be little correlation between the two. In a Turbo Volvo I once owned, I installed an oil temperature gauge. The car had a separate air-oil cooler.

On that particular car, the oil temp was proportional to how hard I pushed it. In the Colorado mountains in the cold, if I was really using the turbo (and I often did), I could see 95C. In the summer in Virginia Beach, driving around in the heat and humidity, it would be at 85C. Pull a trailer in the summer heat, and I would see up to 105C.

So, what's your oil temp run in this car? How do you use it?

IF you track it only, or you really drive it hard, so that the oil temp is high, then yeah, maybe go up...

But don't fall for the logic trap of high air temp = high oil temp. It is often untrue.

 

[spasm3]

Tell us what car and driving style, average trip length.

 

[ThirdeYe]

What kind of car is it for? It sounds to me like if it called for 20W-50, it's probably an older British car? The Firebird we have is a summer only vehicle, so I just use 10W-30 in it since it rarely ever gets started in below freezing temperatures. Plus, it's what GM recommended for the vehicle at the time. I've gone back and forth considering using a 5w30 instead, since I have quite a bit of it from when I still had my old Acura, but the 10W-30 seems like it would be a better option for the type of driving it sees. (and yes, I know 10W-30 isn't always thicker than 5w30, but with Mobil 1 HM it is)

 

[Warstud]

IMO...If it's not ticking at cold startup or hot idle with the 20W50... there's no reason to switch.

 

[Nick1994]

This is a joke, right?

 

[fdcg27]

What are you looking for here?
Would using a 20W-50 in warm weather cause any harm?
No.
Would this grade bring any benefits?
Probably not.
You don't mention what application you're talking about, but most engines for which 20W-50 was recommended back in the day are fine on a 10W-40 or even a 10W-30.
The 20W-50 grade was developed for a very specific application and then came to be recommended for a wide range of British and European cars, whether it was really needed or not.
In short, if you want to run the thick stuff in warm weather, it won't hurt anything, although it may not help anything either.

 

[Whimsey]

My 1996 Contour is our warm weather vacation car. It see 8-10 hours/day at speeds ~75 mph going to Key West from NJ. It calls for 5w30 and I've run that viscosity in it since new using synblends and synthetics. It's garaged/stored from late Oct through April. I was thinking about changing to conventional oil due to lack of miles in a year and using 10W-30 because it usually have a lower NOAK than 5w30 which should be better for more extreme conditions such as hours and hours on end of high speed driving. Thoughts

?

Whimsey

 

[aquariuscsm]

Is it a hot rod/muscle car? I'd stick with the recommended 20W50 in your favorite brand.

 

[fdcg27]

This kind of driving should actually be pretty easy on every part of the car and I doubt that you're seeing really high oil temperatures.
75 mph isn't exactly high speed, unless your Contour has really short gearing.
Certainly using a 10W-30 rather than a 5w30 isn't cauing any harm, but if you want lower NOACK, any syn oil will give it to you.

 

[crazyoildude]

what kind of car?? 20W50 is very heavy.

 

[2KBMW]

If you say that your weekend car's oil grade is 20w50, then use it in summer.
You don't need anything heavier, which is hard to find anyway. Actually, you can get by with 40 weight oil.

 

[Pontual]

IME a conventional 20w50 gives much more varnish then a 20w40, because of VII breakdown. That red stuff decreases a lot with a narrower band.

 

[HerrStig]

Originally Posted By: ThirdeYe
What kind of car is it for? It sounds to me like if it called for 20W-50, it's probably an older British car? The Firebird we have is a summer only vehicle, so I just use 10W-30 in it since it rarely ever gets started in below freezing temperatures. Plus, it's what GM recommended for the vehicle at the time. I've gone back and forth considering using a 5w30 instead, since I have quite a bit of it from when I still had my old Acura, but the 10W-30 seems like it would be a better option for the type of driving it sees. (and yes, I know 10W-30 isn't always thicker than 5w30, but with Mobil 1 HM it is)
Many older BMWs list 20-50 for high temp use.

 

[HerrStig]

Originally Posted By: 2KBMW
If you say that your weekend car's oil grade is 20w50, then use it in summer.
You don't need anything heavier, which is hard to find anyway. Actually, you can get by with 40 weight oil.
I suspect T6 in 5w -40 would be just fine all year.

 

[Quest]

Originally Posted By: Pontual
IME a conventional 20w50 gives much more varnish then a 20w40, because of VII breakdown. That red stuff decreases a lot with a narrower band.


varnish from petroleum based lubricants mainly has to do with the residual stuff after the cracking process, which, as the base oil "decomposes" during cyclical heating (boiling), and turns into varnish and deposits.

Additive packs does the job by balancing the base oil and with detergency to keep the oil from depositing, but can only go so far (some inferior add-packs will not perceived as being effective in keeping the engine clean)

This is particularly obvious if you are on solvent-scrubbed Gp1 base oil, but as the API/ILSAC requirements becomes more stringent, so is the need to up the base lubricant.

Nowadays, no longer does a lubricant based primarily of GpII enough to meet the stringent motor oil requirements, and most conventional motor oil that meets the latest specs are essentially a "semi-syn" blend, comprised of GpII, GpIII and much more.

I came across many domestic blends of motor oil from some asian and mid-east countries that purportedly claimed to be API SN rated, but upon the UOA and close inspection of the conditions of the upper valve train after extended use tells me otherwise.

In other words: they may have short-changed their claims RE: API certified, based on the varnish, deposits, UOA readings.

I wouldn't be at all surprised if that is happening to domestic brands of motor lubricants made in Brazil or Mexico.

Q.