Can oil grade impact cam phasing?

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Jan 23, 2022
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My Chrysler van recommends 5W20 but I just bought some 5W30 because it was on sale. In the past I never figured this would cause a problem or maybe even would be slightly better.

The Pentastar engine uses some kind of cam phasers on the cams. I think it's driven by oil pressure. Could changing oil grades cause a problem with the cam timing?
 
My Chrysler van recommends 5W20 but I just bought some 5W30 because it was on sale. In the past I never figured this would cause a problem or maybe even would be slightly better.

The Pentastar engine uses some kind of cam phasers on the cams. I think it's driven by oil pressure. Could changing oil grades cause a problem with the cam timing?
speaking only at operating temperature, so cold performance notwithstanding, a thicker oil means higher oil pressure. not a lot higher, and probably not enough to be the slightest concern, but it is a factor, and in theory could have an impact on how the cam phasers react. lifters certainly sound a bit different (not worse, not better, just different) depending on what oil is in an engine. i think your assessment that the 5w30 is better is quite correct, purely from a durability perspective. if you don't notice any adverse changes in how the engine runs on that oil, i would consider switching to it for future changes as well to extend the engine life.
 
Does anyone think owning and operating a car in a frigid climate, with constant severe cold starts, is harder on electronic cam phasers? And if so, are they more prone to cam phaser trouble? I would imagine so, if they're as oil viscosity critical as they say.

That being said, there is only just so much tolerance they can design into these systems. I know Chrysler says to use ONLY 5W-20 oil in their 5.7 HEMI V-8 because of this. Using anything thicker can cause it to throw codes. But like "930.engineering" says, you don't start a hot vehicle every morning. So what are we to believe?

What's harder on electronic cam phasers? Living in Miami in June, with 10W-40 in the crankcase. Or living in Fargo in January with 5W-20?
 
No problems to report using ESP 0W30 in my 3.6L Pentastar engine. I've been running a 30 grade in that engine since day 2 of ownership. It's a 2016 and 5W20 is stamped on the fill cap. As others mentioned you're not cold starting an engine with oil which is at operating temperature.
 
What am I missing here ............... there is no dephaser system that operates on oil pressure (hydraulic force) alone (that I have seen) - the oil pressure is used as a driving force via the dephaser solenoid and ECU using the cam position sensor (measured cam pos vs demanded) ................ iow the dephaser stops doing anything soon as the ECU says so irrespective of oil pressure (be it high or low or too high or too low)

Perhaps my dunce hat is on again
 
LvR got it right. The phaser position is controlled by an electronic solenoid that is fed a pulse width modulated signal based on cam position feedback. The computer will simply change the amount of energy being fed to the solenoid to achieve the cam position it wants, regardless of oil viscosity. It the oil is thicker and has more force, it will run the pulses shorter to achieve the final outcome it wants. The problem with phasers, is most have a fine mesh screen in the oil feed or very small oil lines. Sludge can block those lines and starve the phaser to the point it can’t do its job any more. Then you have a problem.
 
If the phaser fails, will it destroy an interference engine? Is there enough adjustment on the phaser to potentially cause piston contact? Or will it just throw a code?
 
I have noticed sluggish running older on Toyota engines with VVTi when thicker oil was used. Not an issue on my Honda Fit that has VTEC which is a step function. The cam phasing design assumes a range of hot viscosity. On the simpler, older toyota design the soloniod goes into a variable cam retard as rpm and galley pressure increases. It has different parameters for cold staring and part of the warmup phase.
for the OP Run the thicker oil if you wish oil give it a couple weeks to shear down to a stable viscosity and report back.
You wont hurt anything, in fact you may pick up more "passing power" .
 
If the phaser fails, will it destroy an interference engine? Is there enough adjustment on the phaser to potentially cause piston contact? Or will it just throw a code?
It is designed with limits to prevent any kind of contact. If that were not the case, the many failures would already have created 'destroyed engine reputations'.
 
I ran 0w40 in our Grand Caravan. Couldn’t tell any difference except it maintained 40psi of oil pressure while cruising according to the EVIC instead of 30 it normally did on 5w20.
 
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