Oil Pressure

jwood0507 · April 14, 2019

Dash

SierraHD17 · April 14, 2019

The dash gauges aren't inaccurate on all the trucks... my 2015 and my current 2017s read the exact same values as the sender is reading on HP tuners. My 15 6.2 was 40 psi at idle with 5w30 and the factory 0w20.

Grumpy Bear · April 14, 2019

36 minutes ago, SierraHD17 said:

The dash gauges aren't inaccurate on all the trucks... my 2015 and my current 2017s read the exact same values as the sender is reading on HP tuners. My 15 6.2 was 40 psi at idle with 5w30 and the factory 0w20.

All the same don't you think it's worth investigating?

SierraHD17 · April 14, 2019

1 hour ago, Grumpy Bear said:

All the same don't you think it's worth investigating?

Not really lol. But if you want to go nuts! For all we know there is something wrong with your trucks stepper on the oil pressure gauge...

Grumpy Bear · April 14, 2019

11 hours ago, SierraHD17 said:

The dash gauges aren't inaccurate on all the trucks... my 2015 and my current 2017s read the exact same values as the sender is reading on HP tuners. My 15 6.2 was 40 psi at idle with 5w30 and the factory 0w20.

Second and third question. Am I reading this correctly, no change in oil pressure (HP tuner) between the 20 and 30 weight oil? Is that your hot idle pressure or cold?

Personally I wouldn't think there would be between grades. Mine didn't show any difference between the two.

SierraHD17 · April 14, 2019

20 minutes ago, Grumpy Bear said:

Second and third question. Am I reading this correctly, no change in oil pressure (HP tuner) between the 20 and 30 weight oil? Is that your hot idle pressure or cold?

Personally I wouldn't think there would be between grades. Mine didn't show any difference between the two.

Correct. If I saw any increase or decrease at idle it was negligible. The only time the truck dropped any appreciable amount was getting the engine hotter than normal and thus higher oil temp when towing. Didn't happen often as that 6.2 half ton was terrible with a trailer behind it.

Edited April 14, 2019 by SierraHD17

diyer2 · April 14, 2019

If there was a problem with oil pressure or flow you would know it quick.

The gauge is a visual aide to give you a feel good feeling.

Lots of cars don't have oil pressure gauges.

Yes, I check my oil pressure because the gauge is there.

You wouldn't know the difference if you didn't have one.

16LT4 · April 15, 2019

The next question is what effect oil viscosity has on the VVT operation. On Fords and Rams, the answer is “quite a bit.” With oil acting as a hydraulic fluid, proper flow long-term is quite important.

Grumpy Bear · April 15, 2019

1 hour ago, dukedkt442 said:

The next question is what effect oil viscosity has on the VVT operation. On Fords and Rams, the answer is “quite a bit.” With oil acting as a hydraulic fluid, proper flow long-term is quite important.

It is the nature of unaerated liquids to be incompressible. It is that feature than permits them to transmit force. Anything past that is application specific. Such as brake fluid's need to deal with insane heat. Viscosity in and of itself hasn't any impact on the transmission of force. It may have something to do with holding a force IF the system lacks seals and relies on controlled leakage in lieu of mechanical sealing to maintain a set pressure required to balance an opposing force such as a spring.

GM uses the same parts in all three Ecotec3 motors and yet specifies two different viscosities. More if you consider those applications outside trucks.

Consider that there is in excess of a ten fold variation in operational viscosity between cold start and fully warmed, on a hot day, where in all parts function normally. There is more than one viscosity grade difference in operational viscosity between lightly loaded and fully loaded caused by temperature where in once again, all things operate normally.

Lastly the oil pump is 'positive displacement' and flow is set by speed driven pump volume not viscosity. Pump volume differs with speed and flow follows. If flow was an issue, within reason, then the VVT would also operate differently at 45 mph than it does at 85 mph given the same gear.

So something sounds odd to me with a manufacture making such a claim.

SierraHD17 · April 15, 2019

3 hours ago, dukedkt442 said:

The next question is what effect oil viscosity has on the VVT operation. On Fords and Rams, the answer is “quite a bit.” With oil acting as a hydraulic fluid, proper flow long-term is quite important.

Little to none. Ford is not any different... they spec multiple viscosities in the 5 liter with no notable changes to cam timing. Oils are changing to help boost fuel economy...not because of mechanical changes..

Edited April 15, 2019 by SierraHD17

diyer2 · April 15, 2019

I'm not going to speculate on oil viscosity.

They spec a viscosity for a reason, I'm good with that.

I have changed oil viscosity after lots of miles to slow oil loss but these were motors with old style lifters.

16LT4 · April 16, 2019

On 4/15/2019 at 12:32 AM, SierraHD17 said:

Little to none. Ford is not any different... they spec multiple viscosities in the 5 liter with no notable changes to cam timing. Oils are changing to help boost fuel economy...not because of mechanical changes..

No experience with the 5.0, but in a 5.4 or a Ram 5.7 I have personally noticed differences in engine running with different oil viscosities, and after seeing the size of oil passages and solenoid screens, it’s easy to see why. Never tried anything but the factory oil in the Chevy.

Edited April 16, 2019 by dukedkt442

SierraHD17 · April 16, 2019

21 hours ago, dukedkt442 said:

No experience with the 5.0, but in a 5.4 or a Ram 5.7 I have personally noticed differences in engine running with different oil viscosities, and after seeing the size of oil passages and solenoid screens, it’s easy to see why. Never tried anything but the factory oil in the Chevy.

I doubt that. I ran 5w30 in an 09 5.7 Hemi and it made zero difference from the specified 5w20. The cars spec 5w40 with the same mds and VVT as well....

Edited April 17, 2019 by SierraHD17

16LT4 · April 17, 2019

6 hours ago, SierraHD17 said:

I doubt that. I ran 5w30 in an 09 5.7 Hemi and it made zero difference from the specified 5w20. The cars spec 5w40 with the same Eagle 5.7 as well....

10 year old engine, different animal. I’ve owned all 3 modern trucks in the past 2 years, and somewhere on my computer have cam timing data for the ram and ford. Thicker oil + small passages = fluid restriction. That’s unarguable. Is GM as susceptible? I have no idea but it’s always something to consider.

But hey hey I really don’t care what the hell people run in their engines, run straight kerosene. Just be aware there are always unforeseen consequences.

SierraHD17 · April 17, 2019

3 hours ago, dukedkt442 said:

10 year old engine, different animal. I’ve owned all 3 modern trucks in the past 2 years, and somewhere on my computer have cam timing data for the ram and ford. Thicker oil + small passages = fluid restriction. That’s unarguable. Is GM as susceptible? I have no idea but it’s always something to consider.

But hey hey I really don’t care what the hell people run in their engines, run straight kerosene. Just be aware there are always unforeseen consequences.

And your 2019 hemi is still the same engine as the 09 lol. Not to mention a 2019 car still specs the higher viscosity oil with the same engine setup the truck runs... but what the hell does Chrysler know... little passages right... yeesh.. But hey... who is counting. It makes no difference and no you can't prove otherwise. But believe whatever tickles your fancy. Its the same reason GM specs 5w30 or higher in the LT1 and 0w20 in the truck L86. And before you say a word about it.. they are part number for part number the identical long block. But those little passages you know.... hahaha.

Edited April 17, 2019 by SierraHD17