5w-30 instead 10w-30

Hey all, I've been using 5w-30 in the 3.4l v6, but I heard that using 10w-30 instead is better in the cold? I'm unsure about it and don't know where I can find the information; any help on the matter is greatly appreciated. I live in a cold area and am just curious if I should use the one that is better in the cold since I'm trying to keep this truck running till I die. On the cap in the engine compartment it says 5w-30

 

5w-30 is manufacturer recommended

 

I'm confused as to why you'd want a thicker oil in the cold?

 

I'm unsure about any of this, I just heard that one of the two is better in the cold and I'm wondering if anyone knows for sure.

 

Do you mean 0w-20 by chance? 10w-30 will be thicker in the cold than 5w-30

 

10W30 is all but obsolete, 5W30 is better in every way and more common to find.

I would personally suggest a high mileage brand in 5W30. I like Castrol

 

Ok I'll take your advice, I used the castrol brand 5w-30 and had no problems I was just curious as to if switching could help at all. Sorry for the confusion.

 

Usually you use thinner. I’m running 15w40

 

I purposely switched to 0W-30 this last change for the winter. I'll see if it's really any better than the 5W-30 I normally use



VISCOSITY

Most oils on the shelves today are "Multigrades", which simply means that the oil falls into 2 viscosity grades (i.e. 10w-40 etc)

Multigrades were first developed some 50 years ago to avoid the old routine of using a thinner oil in winter and a thicker oil in summer.

In a 10w-40 for example the 10w bit (W = winter, not weight or watt or anything else for that matter) simply means that the oil must have a certain maximum viscosity/flow at low temperature. The lower the "W" number the better the oil's cold temperature/cold start performance.

The 40 in a 10w-40 simply means that the oil must fall within certain viscosity limits at 100°C. This is a fixed limit and all oils that end in 40 must achieve these limits. Once again the lower the number, the thinner the oil: a 30 oil is thinner than a 40 oil at 100°C etc. Your handbook will specify whether a 30, 40 or 50 etc is required.

 

I will be curious how the 0W-30 works for you

 

I run 0w-40 year round on 8-9k oil change intervals with excellent analysis results.

 

Maybe these will help.
http://www.upmpg.com/tech_articles/motoroil_viscosity/

https://auto.howstuffworks.com/how-to-choose-the-right-oil-for-your-car-or-truck1.htm

 

The lighter oils are to save gas. They have less protection. Per many online tests heavier oils have better wear properties. So don't go any lighter. I run 10w30 all year long.

 

this.................

 

I remember when a guy I used to work with suggested/told me to put 20w/50 in a RAV4 4cyl since he was going into New England in the winter time. I should've done it since it was a company car and made him look like an idiot, but I know it would've come back to me

 

No.

 

Auto manufacturers have gone to a lighter weight oil for one reason... Federally mandated CAFE (Corporate Average Fuel Economy) standards. The largest loss of HP and fuel economy is friction in the engine / drive train. Synthetic oils can only go so far. Some time ago manufacturers started to experiment with piston ring tension. They learned that if they reduce the tension that the piston rings place on the cylinder walls they can reduce friction. A light tension piston ring cant scrape oil off of the cylinder wall very well so they started to use lighter and lighter weight motor oils. Certain Hondas and Subarus are having to be re-ringed due to they got it wrong... too much oil consumption.

If the manufacturer says use a 10w oil, use a 10w oil.

 

Agreed.

Except for this part:

If the manufacturer says use a 10w oil, use a 10w oil.

At times our beloved federally mandated cafe standard has too much influence on the recommended oil to use from the manufacturers. I posted it up before (not gonna search for it again online) but Toyota will recommend a different oil for the same engine/vehicle in other parts of the world that do not have to adhere to the cafe standards. Realistically, most of the oils anyone uses in North America will be more than adequate. For us OCD types.... That's just not enough. I've analyzed quite a few oil samples of varying weights and makes. But in general, your 5w-30, 10w-30, 5w-40, etc all fall within what Toyota recommends 'globally' with our engines.