6.4L Oil Pressure - Idle vs Cruising

[Dusty]

The filter can definitely affect the oil pressure on a hemi.Oil pressure is measured after the filter on a Hemi,so a poor quality filter can and will affect the pressure.

I'm not sure losing 2 lbs. of oil pressure between different oil filters is a bad thing at idle. The loss of two pounds represents an increase in resistance in the filter. If that resistance is caused by the filter media being finer it also means it is likely trapping smaller debris particles and/or staying under the filter bypass pressure longer.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 105240 miles.

 

[Wild one]

I'm not sure losing 2 lbs. of oil pressure between different oil filters is a bad thing at idle. The loss of two pounds represents an increase in resistance in the filter. If that resistance is caused by the filter media being finer it also means it is likely trapping smaller debris particles and/or staying under the filter bypass pressure longer.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 105240 miles.

When i went to dual remote filters i gained a couple psi of oil pressure from idle on up,because there's less pressure drop across the 2 filters then there is with one filter.

 

[Dusty]

When i went to dual remote filters i gained a couple psi of oil pressure from idle on up,because there's less pressure drop across the 2 filters then there is with one filter.

Sounds right.

For the same reason another commenter said that a larger single filter produced less drop than a smaller one. If the filter media element has increased surface area, there would be an expected reduction in loss at flow.

I lost about 2 pounds at idle when I went to the Fram Ultra, however I still see 53-59 (depending on ambient air temp) at higher RPMs.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 105240 miles.

 

[Slapalax]

6.4L Hemi owner here.

With engine @ operating temp, idle = 35 psi, running = 55 psi. +/- 2 psi depending on outside temp (we get wide temp swings here).

Oil = Red Line 5W-30 (summer), 0W-30 (winter)
Filter(s) = Royal Purple 20-500, Fram XG10060

Your pressures seem nice and high! I also have a 6.4L Hemi, usually get 29-30psi idle at operating temp and 52psi running. I’ve also gone down the rabbit hole of changing around my oil spec, currently running 5W40 (pretty mild PNW climate). At operating temp, my W40 oil should be thicker than your W30 I would think, leading to higher pressure for me, but that doesn’t seem to be the case? Also, I’m running a Fram XG2 right now, somewhat of an experiment. Seems to be exactly the same filter as the XG10060 but larger. Curious about your thoughts on the filter, if you’ve looked into the XG2, and about 5W40 vs 5W30! From other posts, seems like you and I have similar mindsets on these topics, haha.

 

[Wild one]

Your pressures seem nice and high! I also have a 6.4L Hemi, usually get 29-30psi idle at operating temp and 52psi running. I’ve also gone down the rabbit hole of changing around my oil spec, currently running 5W40 (pretty mild PNW climate). At operating temp, my W40 oil should be thicker than your W30 I would think, leading to higher pressure for me, but that doesn’t seem to be the case? Also, I’m running a Fram XG2 right now, somewhat of an experiment. Seems to be exactly the same filter as the XG10060 but larger. Curious about your thoughts on the filter, if you’ve looked into the XG2, and about 5W40 vs 5W30! From other posts, seems like you and I have similar mindsets on these topics, haha.

What 5W-40 are you running as 5W-30 Redline has the rep of being as thick or even slightly thicker then alot of 40 weight oils

 

[HEMIMANN]

Beat me to it, Rick.

SAE viscosity numbers grade ranges - not a specific viscosity. You need to look at an oil maker's spec sheet to find their "typical" property viscosity @ 100 degrees C (engine oil operating sump temperature).

Here's a chart to help you understand: