5w-30 too thick for modern cars?

[3rdGenGuy]

Is 5w-30 too thick for modern cars?

So I recently purchased a 2019 Lexus is350.
It has a 2GR-FKS V6 in it.
Obviously the factory calls out for a 0w-20 oil.
Dealer had new 0w-20 in it, so after 5K miles, I swapped to 5w-30.
I figured running Mobil 1 Extended Performance 5w30 oil was fine since the early 2010s 2GR listed 5w-30 as the recommended oil.
I've run that 5w-30 EP oil in many cars that went above 300,000+ miles.

Within a day, the engine was running oddly.
The exhaust tone on mid throttle sounded weird. Kinda like a drone.
I thought it was leaking exhaust gaskets, but I changed them to no avail.

My brother had mentioned that some modern cam phasers don't like thicker oils. And since it's 50F out, I thought maybe the oil just wasn't flowing right.
So I used an OBD2 scanner to see what the cam angles were.
And sure enough, the cam timing was kind of erratic and laggy.

So I changed the oil to a Mobil 1 Extended Performance 0w20 and the issues are all gone.
No weird noises
Cam timing is consistent
And the car feels more responsive.

I always thought the difference between 0w-20 and 5W30 oil was minimal or non existent.
Apparently not

 

[GW.]

No 5W-30 is not to thick for modern vehicles. Remember in some climates 0W-20 is more viscous than 5W-30. Like in Caribou, Maine from October to April….vs San Diego, California year round.

 

[scrllock]

More likely that you left the oil in too long and new oil helped. Never seen a change to 30 grade actually make a difference in VVL/VVT.

 

[fantastic]

That is not a big enough leap in viscosity to matter much. It may feel a bit slouchy at first moving up a grade but quickly get used to it.

 

[wwillson]

I thought it was leaking exhaust gaskets, but I changed them to no avail.

I don't understand what you mean by you changed them.

 

[SC Maintenance]

Please explain to me how a slightly thicker oil changes how a cam phaser operates? I will wait.

 

[iCurious]

It would be nice to see the live data on the cam timing changing with different viscosities.

 

[Rand]

Something else going on, Maybe you bought someone's problem.

 

[3rdGenGuy]

I don't have a way to record OBD2 data history with the cheap reader I use
Maybe the $2,000+ code reders can do that.
But a guy that I work with used to be a master Toyota technician.
He said that thicker 10w-30 oils can sometimes interfere with VVT systems or variable cam lift stuff.
He said the earlier hybrids were very particular about using thinner oils.

I doubt the oils were left in too long.
Here's the oil test from the dealer 0w-20 and the Mobil 1 Extended Performance 5w30.
lowwr of equal to what Blackstone usually sees in 2GR

I just never realized 5w-30 would be worse than 0w-20

 

[SC Maintenance]

I don't have a way to record OBD2 data history with the cheap reader I use
Maybe the $2,000+ code reders can do that.
But a guy that I work with used to be a master Toyota technician.
He said that thicker 10w-30 oils can sometimes interfere with VVT systems or variable cam lift stuff.
He said the earlier hybrids were very particular about using thinner oils.

I doubt the oils were left in too long.
Here's the oil test from the dealer 0w-20 and the Mobil 1 Extended Performance 5w30.
lowwr of equal to what Blackstone usually sees in 2GR

I just never realized 5w-30 would be worse than 0w-20

View attachment 312114

Your master Toyota technician clearly doesn't understand the concept of closed loop control.

The oil flow only provides a motive force to move the cam's. There position is controlled by the ECU and the loop closed by the CAM sensor. The only way oil viscosity could possibly affect that would be too low of oil pressure not creating enough hydraulic force to move the cam's. If anything thicker oil will cause higher pressure.

Even as such the difference between 20 weight and 30 weight is pretty small at temperature.

 

[JavierH19]

Would you consider a either a new 2024 Toyota Camry V6 or Highlander a modern car?

Simple yes or no, please answer.

 

[GW.]

I don't have a way to record OBD2 data history with the cheap reader I use
Maybe the $2,000+ code reders can do that.
But a guy that I work with used to be a master Toyota technician.
He said that thicker 10w-30 oils can sometimes interfere with VVT systems or variable cam lift stuff.
He said the earlier hybrids were very particular about using thinner oils.

I doubt the oils were left in too long.
Here's the oil test from the dealer 0w-20 and the Mobil 1 Extended Performance 5w30.
lowwr of equal to what Blackstone usually sees in 2GR

I just never realized 5w-30 would be worse than 0w-20

View attachment 312114

There’s a reason your friend use to be a “master tech”….

 

[DKL]

I've done used oil analysis on 3 Honda engines, all of which spec 0w20, and consistently gotten lower wear metals with 0w30 and 5w30 compared to 0w20.

 

[3rdGenGuy]

There’s a reason your friend use to be a “master tech”….

Well that's because we make $70 an hour in a clean room that rivals a ER.
Way easier work for the old timers
I can only imagine how bad working on cars 8hrs a day at 60yrs old would be.

 

[3rdGenGuy]

I've done used oil analysis on 3 Honda engines, all of which spec 0w20, and consistently gotten lower wear metals with 0w30 and 5w30 compared to 0w20.

Could you post the lab results for us?
My test above didn't show any difference in wear from 0w-20 to 5w-30.

 

[Wireman1987]

This is a wild topic. I don’t believe there’s enough difference between a 0W20 and 5W30 especially at operating temperature and 50° F.

??

 

[GW.]

Well that's because we make $70 an hour in a clean room that rivals a ER.
Way easier work for the old timers
I can only imagine how bad working on cars 8hrs a day at 60yrs old would be.

He doesn’t understand how oil temperature affects oil viscosity. VVT can not be viscosity sensitive, if it was our friends in Alaska would be in big trouble…

 

[3rdGenGuy]

I've done used oil analysis on 3 Honda engines, all of which spec 0w20, and consistently gotten lower wear metals with 0w30 and 5w30 compared to 0w20.

Could you post the lab results for us?
My test above didn't show any difference in wear from 0w-20 to 5w-30.

 

[Mechanician]

Doesn't make sense, maybe if it were in sub-zero weather.

 

[3rdGenGuy]

He doesn’t understand how oil temperature affects oil viscosity. VVT can not be viscosity sensitive, if it was our friends in Alaska would be in big trouble…

I can see how thicker oil could mess up a VVT solenoid.
Some have very small oil passages.
Seen a few 1.8L 1ZZ engines run like crap when bad maintenance clogges up solenoid passages.