Ford 7.3 Godzilla Oil Pressure Gauge Installed, Results are in.

[jackreno]

Cold start the pressure jumps to over 60 psi than drops to 28-30 psi at 1200 RPMs than after motor is fully warmed up the oil pressure at 600 RPMs drops to 18-20 psi.
This was only a idle warm up test not driving, will be doing that in about a week.

However testing at different RPMs after warm up the oil pressure does not go above 30 psi till I reach 3000 rpms than it jumps to around 40 psi.

Most my driving is in the 2200 rpm range so I guess it will only be at 28-30 psi, however this test is not driving test, results may change while motor is under load.

The good news is my idle oil psi is not in the very low 8 psi that has been reported by Ford.

My new oi pressure gauge is a electronic type made by Glowshift.

[jackreno]

Just curious from some oil pressure experts is 18 psi good enough at idle for the 7.3.

[jackreno]

Here is a read up about proper oil pressure at idle, 20-30 psi is the normal range for cars, trucks should be 25-35 psi at idle.

That puts the Godzilla at the very low range for oil psi at idle, my oil pressure gauge reads 18-20 psi.

I use Amsoil 5-30 full synthetic with Motor craft oil filter.

https://rerev.com/articles/normal-oil-pressure-at-idle/

At idle, the standard oil pressure gauge should read somewhere between 20 to 30 PSI for cars and 25-35 PSI for trucks. If the pressure is below or above this range, it is considered too low or too high for the engine. Reading your vehicle manual to know your engine’s required oil pressure level is essential. Always watch your oil pressure gauge to ensure it doesn’t exceed the specified range.

If your oil pressure gauge or dashboard sensor reads below 20 PSI at idle, it indicates that your engine’s oil pressure is too low and should be checked immediately to avoid further damage.
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What the heck Ford, a big V8 should have better oil psi at idle.

[PushedAround]

Originally Posted by jackreno

Here is a read up about proper oil pressure at idle, 20-30 psi is the normal range for cars, trucks should be 25-35 psi at idle.

https://rerev.com/articles/normal-oil-pressure-at-idle/

Well, that was a pretty non-informative article. That's what you get when someone with 5 years' experience becomes an expert.

Oil pressure is determined by 3 things:

1) Oil pump capacity
2) Oil viscosity
3) Bearing clearances (never mentioned in the article)

If your rod and crank bearings are beginning to wear, your oil pressure will drop. This is usually seen more at an idle than at higher RPMs, especially as most pumps have pressure relief valves to prevent overpressure at higher RPMs (not really an issue with truck motors) or when the oil is really cold (read thick).

15~20 psi at a no-load idle is acceptable IMHO (40 years of racing experience). More important is what the pressure is under load. Please post your findings.

As an aside, running oil with the next higher viscosity is an old racer's trick to help keep pressure in the system with "looser" bearings.

[SafariBen]

Agree, don't put any value in that article, 18psi hot idle sounds fine to me. If you want to do the "deep dive" into the engine, read on some ford forums what they say about that engine and oil pressure, but only if you do a better job of judging the author than with that article.



Lots of heavy diesel engines have low oil pressure, in that case it's just in the design of the engine. Only if the engine model typically has high oil pressure and yours is low, is there reason to investigate.

[Cajun 143]

High mileage engines can benefit from higher viscosity oil. I can remember decades ago when GM clearly stated 8 to 10 psi at idle was sufficient and 10 psi per 1000 rpm increase was norrmal

[jackreno]

Yea I know the article was a basic oil pressure chart and can be different on certain motors, just was posting that, however 18-20 psi is far better than some reports oil psi on the Godzilla was around 8 psi, I guess some oil pumps fail early and others don't or is it the lifters, who knows.

I installed the oil pressure gauge so I can watch my psi and it also let me know where the idle psi is at, I think all Godzilla V8 owners might want to install a real oil pressure gauge so you can see what is going on.

[jaydee325]

Originally Posted by jackreno

Yea I know the article was a basic oil pressure chart and can be different on certain motors, just was posting that, however 18-20 psi is far better than some reports oil psi on the Godzilla was around 8 psi, I guess some oil pumps fail early and others don't or is it the lifters, who knows.

I installed the oil pressure gauge so I can watch my psi and it also let me know where the idle psi is at, I think all Godzilla V8 owners might want to install a real oil pressure gauge so you can see what is going on.

I'm not sure of the need for a separate oil pressure gauge. Both of our daily drivers have a menu you can scan on the dash display and get engine oil pressure displayed along with engine hours (not miles) etc.

In my experience, if you don't get an MIL and associated scan code pertaining to oil pressure, all is good.

[Flyer15015]

OP does not say what oil he's using, Dino or Syn, or the weight he's using, or if he's using any additives in the oil, so it's hard to comment, but easy to speculate.
My GM 8.1 gets Mobil 1, 10-40 synthetic and a can of Restore each change, and she runs about 60+ psi on a cold startup. That settles down to 35 at a hot idle, and 40 - 42 cruising at 60MPH on a summer day. She does have 55K on the clock.

According to the ford truck forums the new Godzilla motors have a variable speed oil pump and a "dumb" gage that really only senses pressure of any kind. Several of the truck guys have "T'd" a real pressure gage on the sender port and they say you should get 19 -21 pounds at a hot idle. This according to the posters on the Ford truck forum.
A scan gage will not give you this info, so apparently the ECU doesn't know either.

Mike in Colorado

[d23haynes57]

If you into gauges, an important date point is oil temperature. It may be available on the ECU. Some engines may monitor it. For an RV that becomes important. There are some driving conditions that may overcome the capacity of the oil cooling system and allow oil temperature to get out of control. Hi oil temperature will reduce viscosity and oil pressure. It also reduces the ability to cool the pistons from underneath and hot oil carry over can contribute to an engine going into pre-ignition. Oils contribution to low-speed pre-ignition is a focus of the GM Dexos specifications. Another concern is over filling. the top mark on the dip stick is not the full mark. It is the maximum, do not exceed no matter what mark. Best oil fill level is somewhere between the two marks and don't add until just below the lower or add mark.

[jaydee325]

Originally Posted by Flyer15015

OP does not say what oil he's using, Dino or Syn, or the weight he's using, or if he's using any additives in the oil, so it's hard to comment, but easy to speculate.

Mike in Colorado

See post 3 by the OP. Your old chevy is immaterial to the discussion. Things have changed a lot.

[jackreno]

Originally Posted by jaydee325

I'm not sure of the need for a separate oil pressure gauge. Both of our daily drivers have a menu you can scan on the dash display and get engine oil pressure displayed along with engine hours (not miles) etc.

In my experience, if you don't get an MIL and associated scan code pertaining to oil pressure, all is good.

The oil pressure gauge on Fords are a dumb gauge that only reads pressure even at 3 psi the gauge reads normal, as to the menu scan on dash gauge I don't think that is a option on the Ford RV chassis and waiting for a warning light as to oil pressure is to late for me, I like to see what is going on at all times.

[jackreno]

Originally Posted by Flyer15015

OP does not say what oil he's using, Dino or Syn, or the weight he's using, or if he's using any additives in the oil, so it's hard to comment, but easy to speculate.

Amsoil 5-30 full synthetic and motor craft stock oil filter.

I have been putting in extra zinc but not this last oil change, going to send this oil into a lab to have it tested, don't want extra zinc in the test.

[jackreno]

Thanks for all the reply's above, been worrying about my oil pressure since people have been reporting lifter failure on the 7.3 gas, some also reported the idle oil pressure was in 8 psi range and that sounding really bad, glad mine is at least in a better range 18-20 at idle as to the gauge.

I am still in the old school mind set and like to see a higher oil pressure at idle but as many have said it may be ok on newer motors, heck I remember long ago changing out a good factory oil pump to a high output on older V8s to keep the oil pressure high, I guess those days are gone.