5W20 vs 5W30 in the Midwest for a car that frequently takes long trips

[K4fxd]

I can’t imagine running 0w-10 per Lake Speed… I’d like to se that graph…

I went down a you tube rabbit hole.

Anyway here is the video. Somewhere on the Driven website is the chart in a pdf. I didn't download it or I'd post it.

https://www.speedwaymotors.com/the-toolbox/in-the-shop-with-driven-racing-oil-viscosity/30041

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[K4fxd]

To answer the OP's question I'd use 5-30 in a car that takes long trips as the oil will get to a high temp in this situation.

 

[SHOdaddy68]

My 15 GT gets about 4k miles a year and I do my own oil changes annually. When the car was a daily, I still changed it every 4k. I know these new oils are superior to what we had 20 years ago but I can't fathom going 10 to 15k between changes. I'm typically a MobileOne fan and have mixed in a couple quarts of Driven high zinc 5w30 with the recommended 5w20 over the last few changes.

 

[TonyT930]

About to do another oil change and have been seeing that Ford changed from 5W-20 to 5W-30 for the GT.

I’m between the two for my next oil change and am wondering which to go with. The car is in the Midwest, but doesn’t really get driven much in the winter. It also frequently takes road trips (800-1000 freeway miles).

Which would you go with?

5w30 Amsoil Signature series...

 

[sms2022]

Really could not matter less imo but I always go with the thicker oil.

 

[cheetoh]

About to do another oil change and have been seeing that Ford changed from 5W-20 to 5W-30 for the GT.

I’m between the two for my next oil change and am wondering which to go with. The car is in the Midwest, but doesn’t really get driven much in the winter. It also frequently takes road trips (800-1000 freeway miles).

Which would you go with?

They switched it between 2020 and 2021. I have a 2020 GT and started using 5W-30 last year instead of 20. My car was ticking for months and I had no clue why, took it to Ford and they also had no clue why... until I went back to 5W-20 and it went away. Never ran into any problems or anything with 30 besides the ticking, and im on the fence about staying with 20 or going back to 30...

 

[PoCoBob]

Thing to remember is the first number is the thickest the oil will be so if Ford specs 5w-XX then any 5w should work fine.

As I understand it the first number (ie:5) is the weight of the oil, then the add polymers that thicken the oil as it heats up. So if it was a 5W30 oil the oil would thicken up to where it flows like a 30 weight oil, but it's still 5 weight oil. We may be saying the same thing differently but I would read that as the oil will never be thinner than the first number.

 

[CrazyHippie]

About to do another oil change and have been seeing that Ford changed from 5W-20 to 5W-30 for the GT.

I’m between the two for my next oil change and am wondering which to go with. The car is in the Midwest, but doesn’t really get driven much in the winter. It also frequently takes road trips (800-1000 freeway miles).

Which would you go with?

Because the Coyote is a high-performance, hot-running engine, 5W-30 is the better choice. 5W-20 was used to achieve better gas mileage in respone to regulations, not because it was good for the engine. Ford changed to 5W-30 for a reason. I'd be willing to bet that 5W-40 is even better, but in order to maintain the warranty, I'm sticking with 5W-30.

 

[K4fxd]

As I understand it the first number (ie:5) is the weight of the oil, then the add polymers that thicken the oil as it heats up. So if it was a 5W30 oil the oil would thicken up to where it flows like a 30 weight oil, but it's still 5 weight oil. We may be saying the same thing differently but I would read that as the oil will never be thinner than the first number.

Oil is thickest when cold, as it heats up it gets thinner. It is not weight, the W stands for winter.

Using 5w-30 as an example

The additives prevent the oil from thinning to the 5 viscosity grade as it gets hotter. So the oil starts as a 5 grade cold and the additives keep it from thinning further than a 30 grade oil when hot. The test points are 40c and 100c.

If you really want to know more about oil than you ever wanted, watch the Lake Speed Jr videos on oil and viscosity.

 

[Jerryinpa]

I run 5-30 Castrol Edge which is full syn and the best oil Castrol sells, change every 5k miles, at last change at 5k oil reset said 30% left.

 

[WildHorse]

I used 5w40 since the first oil change (mine calls for 5w20) .01 loss mpg be damned.

The BOSS 302 uses 2 grades as per the factory : 5w20 & 5w50.

AFAIK, say with 5w20 ,
the first number can never go up
IE: 5w to 10W .
The second number can never go down
IE: w20 to w10

Due to cold bearing clearances. Bad things will happen.

Remember even at a 100F expansion is miniscule at best.

 

[PoCoBob]

Oil is thickest when cold, as it heats up it gets thinner. It is not weight, the W stands for winter.

Using 5w-30 as an example

The additives prevent the oil from thinning to the 5 viscosity grade as it gets hotter. So the oil starts as a 5 grade cold and the additives keep it from thinning further than a 30 grade oil when hot. The test points are 40c and 100c.

If you really want to know more about oil than you ever wanted, watch the Lake Speed Jr videos on oil and viscosity.

I'm having trouble figuring out your logic. Everyone knows that hot oil is thinner than cold oil. But since all oil viscosities are rated at the temps you mentioned then you need to compare apples to apples. If you test 5 weight, 5W20 and 5W30 at those temps the 5 weight will be the thinnest, then the 5W20 and the 5W30 would be the thickest of the three. So the comment I originally quoted ( Thing to remember is the first number is the thickest the oil will be ) is wrong.

 

[DrZed]

Coyote bearing clearance are very tight. That said the all aluminum engine grows quite a bit when hot.

.... but nothing in a coyote for bearing clearance is actually aluminum no? (except for the cylinder head and camshaft clearance - no bearing)??

Steel crank, main caps, rods etc??? I guess perhaps somehow the block side of the main caps in aluminum could change the bearing clearance to the steel cap??? Am I explaining this right??

 

[K4fxd]

If you test 5 weight, 5W20 and 5W30 at those temps the 5 weight will be the thinnest, then the 5W20 and the 5W30 would be the thickest of the three. So the comment I originally quoted ( Thing to remember is the first number is the thickest the oil will be ) is wrong.

You are correct if you are comparing straight weight oils. 5 would be thinnest at all temps compared to 20 and 30.

Multi vis oils the 5W is tested at low temp (I forget what exact temp) lets say -10c, it will be no thicker than a straight 5. At 40c it will be no thicker than a straight 30 at that temp.

It starts out as a 5 viscosity grade cold, instead of a 30 grade cold, and when it heats up the additives prevent it from thinning to a 5 grade at 40c and 100c. I suppose you could say the additives thicken a 5 grade to a 30 grade when at operating temp.

Just had a long conversation with Brian from BND. We talked about many aspects of oil.


Anyway my point is a 5w cold is many times thicker than a 30w hot.

 

[xcm77]

any as long as they're full synth

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