Too thick: 20w50
Too thin: 5w20
Everything else in between is permissible.
Too thin: 5w20
Everything else in between is permissible.
Thick or Thin,I'm confused?????
- Thread starter Big John
- Start date
- Status
Ah! a diplomat amongst us
Whimsey
"Thick thick, medium thick, or thin thick?"
Recognize that quote? Anybody?
Recognize that quote? Anybody?
AEHaas. Nice educational reply!
What a shame oil temperature, pressure and other gauges, analog or digital, aren't standard/optional equipment on "everyman" cars. It wouldn't be that hard to do; I know, not market reality.
What a shame oil temperature, pressure and other gauges, analog or digital, aren't standard/optional equipment on "everyman" cars. It wouldn't be that hard to do; I know, not market reality.
You probably have oil coolers on your cars.
May I suggest you read SAE Paper 2001-01-1073 Engine Lubrication Model for Sump Oil Temperature Prediction, Zoz, Steve, et al
Patman
Staff member
But your "winter" in Florida isn't enough of a difference in temp to truly see the change. In my Corvette, I see oil temps closer to 207 or 208F at 75mph on an 80F day. In the winter on a 0F day, at 75mph on the highway, the highest I might see is maybe 201F. So it's not a huge difference, but there is definitely a difference. And if I'm just driving around town at lower rpms in the winter it won't get any hotter than 185F, but in the summer it would be closer to 195F.
Another point of note, my computer has been reprogrammed so that my cooling fans run all the time when stopped. So instead of my coolant temp hitting 228F like it used to when stuck in traffic, it now never goes above 192-194. So this does affect oil temp too, since the cooler coolant keeps the oil temps cooler in traffic than before.
- Joined
- Jun 2, 2003
- Messages
- 23,587
I hope they are lubricated well. I see no problem with using a synthetic 5w30 with HTHS =/>3.5.
- Joined
- Jun 2, 2003
- Messages
- 23,587
Too low oil pressure at high RPM may also indicate worn crank bearings. A little late to change to a thicker oil.
For your information, I have experienced oil pressure lost after sustained high-speed driving right when getting off the Autobahn. That happened with a full synthetic 5w30 oil in my '89 VW Scirocco. After switching to a 10W-40 it never again happened, despite the same type driving. It did however again happen to me in a rental car over there a couple years ago. The poor thing had only under 10k km on the clock!
Is that such a good idea? I'm not sure those electric fans were designed for a 100% duty cycle like that. Maybe consider letting coolant temps reach 205* before using the fans. They'll be on a lot less.
Patman
Staff member
When I originally got my dyno tune done I asked for the high speed fan setting to be set to come on at 200F and off at 195F, so they weren't running all the time, but for some reason it didn't take when he downloaded the program. I am getting it redone in the spring so I will be getting that readjusted.
But also keep in mind, GM's programming is set up to completely shut down the fans at speeds above 35mph, so no matter how you set up the cooling fans, they will always shut down at those speeds. So they really aren't running at full speed 100% of the time. During the first few minutes of operation they also don't run, as they won't kick in until about 190F.
Thank you Mr Hillary..As I said I am unfamiliar with the intricacies of engine oil and want to do good by my engine..I assumed that everyone did used oil analysis to find the best oil for their application,now I get asked what I am going to look at to see if my engine likes one better or not,so now I am just totally confused...Can I tell by uoa that one oil is better than the other????
Thanks Patman for confirming the real oil temp. differences winter to summer. There is no way the oil temp. will be higher in the winter than the summer.
And the truth about thicker viscosities is they're design for/help/perform better at higher temperatures and NOT the reverse thinking.....ie. use a thinner lube to lower your oil temps...
And the truth about thicker viscosities is they're design for/help/perform better at higher temperatures and NOT the reverse thinking.....ie. use a thinner lube to lower your oil temps...
If you look at Ford's TSB on oil recommendations they specifically state that that 5W-20 is recommended for fuel savings. As I recall they state that 5W-20 or 5w30 is recommended for use in a specific list of vehicles, 5W-20 is noted as not being acceptable for use in some specific vehicles, and not in vehicles that are excluded from the ok to use list.
In summary it seems that if you value fuel effeciency over other attributes then 5W-20 is a good choice if your vehicle approved for such oil. Note that you should also try to check what are oils being used in other parts of the world in your vehicle, as heavier oils than 5w30 are used in some areas even though 5W-20 could be recommended in the US.
In summary it seems that if you value fuel effeciency over other attributes then 5W-20 is a good choice if your vehicle approved for such oil. Note that you should also try to check what are oils being used in other parts of the world in your vehicle, as heavier oils than 5w30 are used in some areas even though 5W-20 could be recommended in the US.
Another idea for selecting oil thickness. At the tail end of an oil change interval I drained off 40 oz from a 4.5 quart system on my wife's '92 3.0 V6 Aerostar (105,000 miles) and installed 40 oz of 15w50. This vehicle always had 30 weight. I had been topping with the 15w50 and then some Synpower Oil Treatment. It ran fine on straight 30 weight (10w30) at 10.9 cSt 100c viscosity, fine all the way up to about 13 cSt (a very light 10w40), but currently it is up to 14.3 cSt and it feels like the parking brake is left on lightly when I drive it. Perhaps a sign the oil is too thick? Also the engine noise seems deeper toned. Think I will back off to about 12-13 cSt, a nice 10w30/40 borderline mix
.
Changed from a 15.5cSt forty-weight to a 12cSt thirty-weight.
New air filter
New fuel filter
Inflated tires to a more "ideal" pressure.
My parking brake is off now...
Trotsky = Born Lev Bronsteinquote:
Originally posted by 427Z06:
quote:
Originally posted by Whimsey:
This is a great site with lots of diverse opinion and facts. Let's not resort to nasty name calling. In case you didn't know from your commie professors, Trotsky, a fellow Bolshevik, was executed in 1940 in Mexico on the orders of Stalin, the darling of America's intelligentsia yesterday and today. If you're going to try to insult people for imposing their views on this site at least get it right and call us fascists. A college education today is woefully lacking. The leftists teaching in colleges today can't even get their fellow leftists straight
Whimsey
Apparently my slacker Austin friends are at least well educated. They correctly call me a fascist on a regular basis.
Bingo,you hit the nail on the head my friend!!! I have been on a quest for the holy grail of oil.I haven't bought into the GC craze,searched the synthetic world for the optimun oil wether it be brown,purple,red,blue or what have you...Well the search is over I'm running Mobil 1 0w40 in my 5.3 year round and Mobil 1 0w30 in my wife's 3.8,readily available,reasonably priced,plus the buy 3 get 3 deal,the search is over..... anybody want to buy some RP???????
Thanks for the info...I am sure my choice's will work out just fine..
- Status
Similar threads
- Locked
- Locked
- Locked