Oil Pressure Increase After Filter Change

Hello All,

Does anyone know exactly where the oil pressure is measured in a 2014 5.7 Hemi?

I just bought the truck and changed the oil and filter (5W-20 full synthetic and a FRAM XG2 synthetic filter). The oil pressure immediately went up about 4.5 lbs after the oil/filter change. My thinking is that if the oil pressure is measured before the filter, then my new filter resists oil flowing through it more than the old one, and I might be getting less oil into the galleries. However, if the pressure is measured after the filter, then the new filter is probably passing more oil into the oil galleries.

Thanks in advance for your advice,

Terry

Use Royal Purple filters and you won't have to worry about that

I think it's a good question. There's other members including myself who noticed different oil pressure with different filters. I used RP 20-820 and there is a definite increase in oil pressure. I have a stock size Fram at the moment and noticed a drop in warm idle pressure compared to the RP filter.

Yes. Regardless of filter brand, I'd like to know what's actually going on in the engine. Thanks for the responses so far.

Taspeace said:

Hello All,

Does anyone know exactly where the oil pressure is measured in a 2014 5.7 Hemi?

I just bought the truck and changed the oil and filter (5W-20 full synthetic and a FRAM XG2 synthetic filter). The oil pressure immediately went up about 4.5 lbs after the oil/filter change. My thinking is that if the oil pressure is measured before the filter, then my new filter resists oil flowing through it more than the old one, and I might be getting less oil into the galleries. However, if the pressure is measured after the filter, then the new filter is probably passing more oil into the oil galleries.

Thanks in advance for your advice,

Terry

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Oil pressure is measured after the filter. I think your Fram filter has a rep of letting rocks through.

Higher initial viscosity = higher pressure. regardless of the previous rating of the old oil, those fluids get tired.....And new oil rated at the same as the oil oil may in fact be more viscous. this also applies to differences between brands.

CheechDogg.0n37s said:

Use Royal Purple filters and you won't have to worry about that

Click to expand...

or any other filter manufactured by Champion Labs. The list is long and distinguished.

I'm not even sure if the oil pressure "gauge" display on these are a true gauge versus just a pressure switch. Basically it just says do you have oil pressure or not and then the ECM calculates what is should be. That is not that uncommon on newer vehicles and I know for a fact as some points in time that was the case on these trucks. To be honest I think people tend to put WAY too much thought into oil filters and such. Also keep in mind that the oil pressure really isn't what is important but rather the volume of oil going through the engine. Just because the pressure is way high doesn't mean you are getting good flow. The system could be all stopped up and just letting a pinhole size amount of oil through and cause high oil pressure.....theoretically having a little higher pressure could mean the filter has more restriction which is causing the higher pressure, but has less flow or volume. Think about if you have just an open ended garden hose, have you ever put your thumb partially over the end of the opening to restrict the flow but get the pressure higher so the water shoots out further? The only reason you use the pressure is it's the easiest way to measure if you have oil moving. It's much more difficult to measure volume or flow. Same reason you measure air pressure in tires as it's really the volume of air that is important, but it's really hard to measure the volume of air in the tire and really easy to measure pressure.

CheechDogg.0n37s said:

Use Royal Purple filters and you won't have to worry about that

Click to expand...

Well, it has been noted the 10-48 spec'd for later 4 gens has oil pressure problems but the famous 20-820 does not, so to be more correct if I may be so bold to say also consider the larger filter that allows less restriction of flow. 20-500 is also similar to the 20-820 is there is a supply side issue.

However, the Fram XG2 is the large Fram option over the smaller Fram 10060 and the single filter that goes head-to-head against the RP 20-820. Maybe it is a bad filter or something else, but I'm not sure being 4 psi higher is that bad especially at idle if the truck isnt throwing a code.

Interesting, I normally use the XG10060 and have been wanting to try the XG2, but they seem to never be in stock when I check.

EdGs said:

Interesting, I normally use the XG10060 and have been wanting to try the XG2, but they seem to never be in stock when I check.

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I'm running the XG2 on my 09. They're available at Canadian Tire here in Canada for about $16, but it does go on sale (I think I paid under $14).


I can look at my trends later today, but assuming the value is calculated, I'm seeing 25-48psi with RP 5w30 and the XG2. I'll see if I can snag a photo today from a "cold" start (It's 28°C today)

I read about 51 cruising with an XG10060 and PP 5w-30. Pressure is 37 - 41 at warm idle in traffic.

2015 1500 SLT QC 5.7L 2WD 8SPD 146k miles

Thanks, Burla. I looked up the "famous" 20-820 and it looks excellent. My original question, however, remains because if the oil pressure is measured after the filter, then it means that my new filter/oil combination is passing more volume through the filter than the old filter/oil combination. That would be good, and it might just be due to the fact that the XG2 is larger than the previous filter, as you mentioned. Also, I'm thinking that the Chrysler engineers would be smart enough to measure oil pressure after the filter, so that the gauge shows the pressure within the engine, not just pushing up against a potentially clogged filter with a failing bypass valve. So, I might have answered my own question, but I would like to be sure.

I also did a long engine flush before changing the filter/oil, so that might have marginally contributed to the change in pressure, but I'm pretty certain that the filter is the primary reason that more oil is moving through my engine.

Added later: I now see that Wild One already answered my question earlier. The pressure is measured after the filter.

Here's some data I grabbed from my AlfaOBD logs from yesterday. Unfortunately it's not a lot of samples, but should give you an idea.

Thanks, XBrav. This is helpful. Also, I bought my XG2 online from Wallmart. I hope that helps.

Wild one said:

Oil pressure is measured after the filter. I think your Fram filter has a rep of letting rocks through.

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These FRAM filter are just fine, you guys who constantly hammer FRAM and do your Royal Purple or AMSOIL, or whatever need to actually really look into the specs as see how wrong you have become. But hey makes you look big and bad, right??

Burla said:

Well, it has been noted the 10-48 spec'd for later 4 gens has oil pressure problems but the famous 20-820 does not, so to be more correct if I may be so bold to say also consider the larger filter that allows less restriction of flow. 20-500 is also similar to the 20-820 is there is a supply side issue.

However, the Fram XG2 is the large Fram option over the smaller Fram 10060 and the single filter that goes head-to-head against the RP 20-820. Maybe it is a bad filter or something else, but I'm not sure being 4 psi higher is that bad especially at idle if the truck isnt throwing a code.

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Yes, I should of mentioned the 20-820 filter over the 10-48 ... I have only ran the 20-820s on my truck ... fawken love them !

boblonben said:

These FRAM filter are just fine, you guys who constantly hammer FRAM and do your Royal Purple or AMSOIL, or whatever need to actually really look into the specs as see how wrong you have become. But hey makes you look big and bad, right??

Click to expand...

I'm no fan of Fram filters ,as i had a Fram filter cost me an engine at -30F when the filter ballooned and dumped all the oil on the ground,and all Fram offered up was a few filters. Maybe they've improved,but i'm still leary of using them at -30 on a cold start

What is the consensus of a good oil pressure, low/high/average?

I run PUP 5w30 and usually a 20-820 but have a 20-500 at the moment.

At cruising speed I see 60-61psi, warm idle is 44psi in gear and 46psi in neutral. Before getting up to temp my pressure will reach into the mid 70s, but I try to go easy until up to temp.

I live in central Texas and have been cruising in temps at 100 to 108 lately and still see the same psi.

Does this seem to be an issue?

^^^I believe mine are right around there but I run PUP 0W40 and a Fram XG2.