Do different weight motor oils really affect the car THAT much or is it just preference?

My car suggests 5W-20, but if I use, say, 5W-30, what's the harm? Will I damage the engine somehow? What other negative consequences might result? What about using higher viscosity oils for ';older'; engines? Is that recommended or does it do any good?Do different weight motor oils really affect the car THAT much or is it just preference?
everyone else SHUT UP


sorry Dodge man and the other guy.. Eric. I did give you a thumbs up vote


OIl 101;


First and foremost the major difference in oil is viscosity the bigger the single digit oil the slower it will run this holds true at any temperature.


Then there are multi viscosity oils. In an effort to simplify the issue, they take really thin oil that is easy to pump and will flow in every nook and cranny that needs oil (when it is cold) and add some “gunk” that makes it stiff and sticky when it is hot. This is a very very good thing.


The major reason why just about every manufacturer changed to a standard 5w-*.* oil was to improve cold start up lubrication. The minor reason is because the oil is easy to pump there is less wear and tear on the pump and its drive system. And on the + not the thinner oil does not take as much gas to pump around and around.


Manufacturers choose an average operating oil that should match the engine under average conditions, so they usually use a *.*w- 20 to 30 oil. This is an all around good oil. Forced induction engines usually go with a 30 to 50-weight oil because they run hotter because of the extra load and heat generated by the supercharging system (turbo or belt). They need the thicker oil to stick to the parts because at the higher temp it is not as “runny”


If you would like to see the + affects rebuild an engine and try to break it in using a true synthetic or an oil such as GTX 20w-50. IT TAKES FOREVER FOR THE RINGS TO SET this demonstrates the superior lubricating properties.


On the Negative side. Run a 20w-50 or straight 50 in a car and see how long it takes for the oil pressure to come up to normal………….. FOREVER. This happens because the cold oil is cavitating in the pump and it is not lubricating the engine at that time. This gets worse and worse, as the temp gets lower.





Another problem is this. Take an older engine that has a trimming belt that should have been changed more than a few miles ago, (most say 60,000 miles) and start that car up at 0 F…… see how many times you can do that without breaking the belt and I will say that you have more guts than I do.





In conclusion:


If you are the person that lets a car heat up in the winter till the windows are nice and clean, then drive a 50+-mile commute, use thicker oil. And change it every 4,000 miles


If you just love to turn that key and give it Hell for 3 miles on the way to work go a smidge thinner. And change it every 2,000 miles


In any event the in both cases the engines will run as far or longer than normal.





20w-50 is race oil that you can use on the street and is mostly hype. Synthetics are very good but mostly just cost the same in the long run as replacing the engine after about 200000 miles. So do what you want. If you are average use the book if your not average USE YOUR HEAD





just to make a point about everyone with there engines


factory stock 1963 rambler 660 classic with a 287 V8 345,000miles


never opened but 2 timming chains and one oil pump.and 4 water pumps 10w-40


1996 Olds 88-Royal 290,000 miles Synthetic. a timming chain and 10w-40


1986 omni 2.2 GLHS turbo (275hp) 20w-50 win the winter and straight 50 summer


1996 Sable 176,000 75hp nos wat kit and 10w-30 summer and 5w-30 winter (cracked the heads but that is not an oil issue)


and about the ';garontee';


I have never ever met a ';mechanhick'; factory trained or collage educated or otherwise that even new about a viscocity meter let alone use one. or even know how to change a Ford viscocity time into an SAE oil wieght.


PS


sorry Dodge man and the other guy. I did give you a thumbs up voteDo different weight motor oils really affect the car THAT much or is it just preference?
The different weights in multi viscosity oils have to do with how thick or thin they are at various temperatures.





For an explanation on how oil viscosity is labeled on the container, follow the first link below. For you overachievers, follow the second link.





I would stick with the manufacturers recommendations rather than trying to second guess the engineers that designed the engine
none of the oils you mentioned wont harm the engine they recommend the thinner oils because the lubricate a lot better that's all,a thicker oil has to warm up before it will flow good a thinner oil doesn't, it will flow good when cold,if you car runs good on the 5-w-30 id stay with it,its a good oil especially if your in a cold environment ,the thinner oils is better to have in it,good luck with it.
Its like low calorie mayonnaise. Its better yea but will it make a noticeable difference probably not.
The viscosity of motor oil tells how readily it will flow. A multi-viscosity oil is designed to flow differently depending on the temperature. The first number is the ';cold'; value and the second number is the ';hot'; value.





5W-20 oil is thinner than 5W-30 oil. The ';cold'; value is the same, but the ';hot'; value is higher. In other words, 5W-30 will be thicker when it's hot than 5W-20.





My recommendation: stick with the 5W-20. That's what your car's engine was designed to operate most efficiently on.
You should really use what the manufacturer of your car suggests. That is what your engine call for!
use th recommended numbers... if you use a thicker oil then the engine will have to work harder to pass it.. if you use a thinner oil it might burn out to quickly..... in the winter you dont want a thick oil because it takes too long to heat up and can damage your car.. good luck
Between those 2 I wouldn't sweat it much.





The manufacturer doesn't go into it, and for good reason, they want people to be satisfied with the car, so they keep it simple and safe.


The W is for winter. 5W-30 for example is a multi-viscosity oil. It is actually 5 weight oil, quite light. And it thickens to 30 weight when hot. This makes starting easier in cold weather. But for proper protection that engine needs thicker oil.


This is the main reason they recommend changing oil every 3000 miles. The ingredients that cause the oil to thicken begin to fail by that point, and you will be left with the 5 weight base oil, which isn't good enough.





Engine age doesn't mean much. Engine condition is everything. Lot's of stop and go is rough on the engine and a little heavier oil can prolong the life.


There's a slight horsepower advantage with lighter oil.





I recommend, if you make it a point to pay attention, to use straight weight oil, 30 weight, except in winter, where 10W or 5W 30 is a much better option. This is best especially if you're bad about regular oil changes. You'd be surprised how


much additional life you can get out of the engine by doing that.





If it doesn't have one now, get an oil plug with a magnet.





Incidentally, I had about 330,000 on my '81 Delta 88 and a little over 200,000 on my '93 Bravada (which I broke, threw a rod racing one night) 128,000 now on the Blazer, runs perfectly. I've never had a car with less than 100,000 on it.
You are pretty well on track. 5w-30 is fine. older engines do use higher vis. to prevent oil burn and leaking.


In the winter you might go to a lighter oil. though 5w is pretty light.
to keep waranty stay with the recomendations dont use additives check with the dealer to be safe
the reason they recommend 5w20 is it will give you slightly better mileage... nothing bad will happen if you use 5w30. as for higher viscosity for older engines- get an oil pressure gauge and watch it... if the oil pressure is low (under 15psi warm) you may want to switch to a heavier oil, or if it burns oil- switching to a heavier oil may slow down oil consumption. if it has good oil pressure and doesnt burn oil then dont worry about it.
It doesn't really matter as long as you don't go too thick or too thin. the thickness of the oil can affect running temps so if the oils too thick you'll use more juice.


don't laugh it's true.


stick to the manufacturers specs, unless youve suped it up in which case youll need a high performance oil(a thicker one)