2018 GT PP Oil Pressure

[FISHTAIL]

So, I recently traded in my 16 GT PP for an 18. While trying to find an under car rattle yesterday, I noticed Fords fantastic new plastic pan on my 18 is leaking already (just over 1k miles). So this morning, I paid more attention to my oil pressure gauge in this car than I have in the past and I noticed it's quite different than my 16.

On my 16GT, cold start oil pressure would be around 90psi, eventually settling to 20-25psi after it warmed up. Pressure would obviously increase with RPM.

On the 18GT, cold start oil pressure was like 60. I accelerate lightly and it jumped to 100, then when I stopped at the bus stop for the kids, it dropped to 20. After it warmed up, idle pressure was more like 15, and pressure didnt' seem to move smoothly with RPM.

I suspect the sending unit is probably just bad, or (and the reason I made a post) Ford decided to make the gauge operate more like a dummy light? Has anyone else with an 18 noticed a difference from the earlier models? Or if you didn't have one, does yours behave like mine?

I need to take the car in for the oil leak now anyway, so I'm trying to determine if this pressure gauge behavior is normal, or if I should have them run that down too. If it's the sending unit, I'm fine with them fixing it. If it's the gauge...I'd rather them leave it. My car doesn't have any rattles inside like my 16 did, and I'd prefer to keep it that way.

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[DickR]

I think what you are observing is normal for the 18 GT. Mine does this and I think others have also experienced/reported similar pressures. Given the consistency of how mine performs I doubt that there is a defective part. This seems to be an "as designed" situation.

When the engine is warm at about 3K rpm ("about" since it seems to vary) the oil pressure literally jumps from the specified 40 psi at 2K to around 80 or more psi if I raise the rpm with the throttle or downshift while at very light throttle to 3K or so. Conversely when I upshift to low rpm the pressure slowly drops back to the 40 psi range.

In "normal" moderate acceleration with automatic shifting of the 10 speed pressure is in the 60 - 80 psi range per a brief check today.

This is with fully warmed factory fill and now with 5w-20 Mobil 1. I don't recall this happening with my 15 GTPP. Both with Motorcraft filters.

The FSM and the parts manual both show a new oil system part for the 18 5.0: "Oil Pressure Control Solenoid" which appears to be a bolt on to the oil pump oil filter/cooler adapter. The FSM and "the internet" don't have any explanation that I can find so I can only speculate that it is used to increase flow and/or pressure with rpm or more likely now that I think about it to decease it at low cruising rpm for fuel economy. My 15 GT's pressure "behaved normally" so I don't remember what it did. The 18 is actually acting as if the solenoid might be keeping the pressure lower than the pump would otherwise deliver with warm/hot oil when the normal higher pressure isn't needed for either bearings or the Ti-VCT cam timing control. Basically it is behaving like an intelligent oil pressure relief valve.

I did find some reference "on the internet" to a solenoid which Ford and others have used with variable vane oil pumps but the 5.0 doesn't have a variable vane pump from what I can see in the FSM.

Per the FSM wiring diagram the solenoid has two wires with one "hot" and the other to a connector on the PCM.

The previous low oil pressure and low oil level sensors are still shown.

The solenoid is 2 wire. Power is through a 15A fuse. PCM connection is labeled UO2SHTR21.

NOTE: My engine has no rattles or similar strange noises at idle or other speeds (stock normal exhaust with engine cover and sound tube intact). About 2300 miles with lots of over 7K rpm blasts on the street and in autocross after a 1K mile break-in.

Also, regarding the oil "leak" there were some signs of oil near the drain plug on mine but nothing that would appear to be from a leak. There were also a couple of oil smudges on the oil filter. Certainly no oil drops on the garage floor or any oil usage showing on the dipstick.

Edit to add: Knowing my dealer and the senior tech who did the pre delivery inspection, etc. the "smudges on the filter" could have been the tech making sure it was tight!

 

[FISHTAIL]

I think what you are observing is normal for the 18 GT. Mine does this and I think others have also experienced/reported similar pressures. Given the consistency of how mine performs I doubt that there is a defective part. This seems to be an "as designed" situation.

When the engine is warm at about 3K rpm ("about" since it seems to vary) the oil pressure literally jumps from the specified 40 psi at 2K to around 80 or more psi if I raise the rpm with the throttle or downshift while at very light throttle to 3K or so. Conversely when I upshift to low rpm the pressure slowly drops back to the 40 psi range.

In "normal" moderate acceleration with automatic shifting of the 10 speed pressure is in the 60 - 80 psi range per a brief check today.

This is with fully warmed factory fill and now with 5w-20 Mobil 1. I don't recall this happening with my 15 GTPP. Both with Motorcraft filters.

The FSM and the parts manual both show a new oil system part for the 18 5.0: "Oil Pressure Control Solenoid" which appears to be a bolt on to the oil pump oil filter/cooler adapter. The FSM and "the internet" don't have any explanation that I can find so I can only speculate that it is used to increase flow and/or pressure with rpm or more likely now that I think about it to decease it at low cruising rpm for fuel economy. My 15 GT's pressure "behaved normally" so I don't remember what it did. The 18 is actually acting as if the solenoid might be keeping the pressure lower than the pump would otherwise deliver with warm/hot oil when the normal higher pressure isn't needed for either bearings or the Ti-VCT cam timing control. Basically it is behaving like an intelligent oil pressure relief valve.

I did find some reference "on the internet" to a solenoid which Ford and others have used with variable vane oil pumps but the 5.0 doesn't have a variable vane pump from what I can see in the FSM.

Per the FSM wiring diagram the solenoid has two wires with one "hot" and the other to a connector on the PCM.

The previous low oil pressure and low oil level sensors are still shown.

The solenoid is 2 wire. Power is through a 15A fuse. PCM connection is labeled UO2SHTR21.

NOTE: My engine has no rattles or similar strange noises at idle or other speeds (stock normal exhaust with engine cover and sound tube intact). About 2300 miles with lots of over 7K rpm blasts on the street and in autocross after a 1K mile break-in.

Also, regarding the oil "leak" there were some signs of oil near the drain plug on mine but nothing that would appear to be from a leak. There were also a couple of oil smudges on the oil filter. Certainly no oil drops on the garage floor or any oil usage showing on the dipstick.

Edit to add: Knowing my dealer and the senior tech who did the pre delivery inspection, etc. the "smudges on the filter" could have been the tech making sure it was tight!

Awesome response. Thanks for the info, I won't worry about that gauge then, I'd just noticed it was different behavior from my 16 and was wondering if that was something I should bring up or not. Sounds like not.

The engine in my car actually sounds fine also. I do have a reasonably loud rattle now, that got louder when I installed an aftermarket exhaust. So I think it's something under the car picking up the vibrations that is now louder because the vibrations are stronger. It was looking for that rattle that caused me to spot my oil leak. I can't hear a thing under the hood, but I can hear that rattle under the car. When I put my head down there, I could hear it coming from the bell housing area, which is when I saw the oil drips.

So far, the level on the stick looks good, but it's clearly leaking. It's left a few spots on my driveway already (which I'd thought were my wifes 190k explorer originally), and at work. So my pan definitely appears to be leaking..I have pics of it on the 2015 Mustang FB group, but I didn't bother hosting them to post here. Not real excited about having the dealership drop my oil pan already, but it is what it is I guess.

I haven't cleaned it all off to make sure it comes back (that's next) but I'd be surprised if it didn't.

Thanks for the info on the gauge...an active pressure control solenoid would explain the quick changes in pressure I saw this morning that made me wonder if my sending unit was wonky. Since it's not making any funny noises, and your seeing similar pressures, I won't pay it any mind.

BTW, how is it in autox? I'll take mine a couple of times this year after work settles down a bit. I really want to have some fun with these tires before I put all seasons on it for DD use.

 

[DickR]

Awesome response. Thanks for the info, I won't worry about that gauge then, I'd just noticed it was different behavior from my 16 and was wondering if that was something I should bring up or not. Sounds like not.

The engine in my car actually sounds fine also. I do have a reasonably loud rattle now, that got louder when I installed an aftermarket exhaust. So I think it's something under the car picking up the vibrations that is now louder because the vibrations are stronger. It was looking for that rattle that caused me to spot my oil leak. I can't hear a thing under the hood, but I can hear that rattle under the car. When I put my head down there, I could hear it coming from the bell housing area, which is when I saw the oil drips.

So far, the level on the stick looks good, but it's clearly leaking. It's left a few spots on my driveway already (which I'd thought were my wifes 190k explorer originally), and at work. So my pan definitely appears to be leaking..I have pics of it on the 2015 Mustang FB group, but I didn't bother hosting them to post here. Not real excited about having the dealership drop my oil pan already, but it is what it is I guess.

I haven't cleaned it all off to make sure it comes back (that's next) but I'd be surprised if it didn't.

Thanks for the info on the gauge...an active pressure control solenoid would explain the quick changes in pressure I saw this morning that made me wonder if my sending unit was wonky. Since it's not making any funny noises, and your seeing similar pressures, I won't pay it any mind.

BTW, how is it in autox? I'll take mine a couple of times this year after work settles down a bit. I really want to have some fun with these tires before I put all seasons on it for DD use.

Thanks for the thanks! I certainly hope my speculation is correct. Fingers crossed. Good luck with the oil leak. If you get lucky it might be a bad drain plug o-ring. Again, fingers crossed.

Car was great at a big SCCA autocross (SCCA Match Tour at ZMAX near Charlotte, NC). Lot of runs in an EVO TnT plus the a total of 11 runs in the two day event. Learned how to use the 10 speed and was amazed by the grip of new RE-71R's and MagneRide compared to an old RE-71R set last year on my 15. I've been an autocrosser since the 1970's and used to be very fast. Emphasis on used to be. Now I'm well past my prime trying to have an enjoyable time. See the FS autocross thread for details on the 2018 in autocross.

 

[FISHTAIL]

Thanks for the thanks! I certainly hope my speculation is correct. Fingers crossed. Good luck with the oil leak. If you get lucky it might be a bad drain plug o-ring. Again, fingers crossed.

Car was great at a big SCCA autocross (SCCA Match Tour at ZMAX near Charlotte, NC). Lot of runs in an EVO TnT plus the a total of 11 runs in the two day event. Learned how to use the 10 speed and was amazed by the grip of new RE-71R's and MagneRide compared to an old RE-71R set last year on my 15. I've been an autocrosser since the 1970's and used to be very fast. Emphasis on used to be. Now I'm well past my prime trying to have an enjoyable time. See the FS autocross thread for details on the 2018 in autocross.

Welcome. There is an oil trace above the plug, so unfortunately whatever it is came from above that spot.

I mostly autox on occasion for fun also, I'm no where near the fastest guy out there. In fact, I'll mostly be auto crossing my fox, which doesn't have a prayer of being competitive anyway...even with the MM setup.

I'd like to play with the 18 to see how it does compared to my 16 last year. I ran the 16 on all seasons, which was FAR from fast, but really quite fun because I was sliding all over creation.

 

[glmarker]

What type of oil pressure are you folks seeing when hot? My new 18 with about 200 miles on it reflect hot oil pressure of about 30PSI at speed and about 20 or less at idle. Not sure if I have a problem or not as I have been unable to find what normal pressures are for this vehicle. Only had it 2 days, so haven't had much opportunity to dig yet. but the low numbers concern me.

Gary

 

[KevinG]

Could you put a 15-17 oil pan on your '18 if these composite oil pans keep giving issues?

 

[Infidex]

What type of oil pressure are you folks seeing when hot? My new 18 with about 200 miles on it reflect hot oil pressure of about 30PSI at speed and about 20 or less at idle. Not sure if I have a problem or not as I have been unable to find what normal pressures are for this vehicle. Only had it 2 days, so haven't had much opportunity to dig yet. but the low numbers concern me.

Gary

I start up in the morning and it's 30-40 on a cold start, but keep in mind cold may be 60-80 degrees out, it drops down to 20-25 once idle is at a warm idle RPM (600s). I haven't paid attention too much while driving, but it stays a lot lower than you would think, and talking to others on here, that seems really normal on the 2018. I have 1300 miles now, no issues, and it's been this way since day one. The 2018's use 10 quarts of oil on the 5.0, it's a new gen 5.0, so I'm sure there are some some things that are driving the difference in oil pressure but I wouldn't be alarmed, from what I've read and discussed with others, it's normal.

 

[DickR]

What type of oil pressure are you folks seeing when hot? My new 18 with about 200 miles on it reflect hot oil pressure of about 30PSI at speed and about 20 or less at idle. Not sure if I have a problem or not as I have been unable to find what normal pressures are for this vehicle. Only had it 2 days, so haven't had much opportunity to dig yet. but the low numbers concern me.

Gary

Per FSM

Oil pressure @ idle with engine at normal operating temperature 10–15 psi (69–103 kPa)

Oil pressure @ 2,000 rpm with engine at normal operating temperature 30–40 psi (207–276 kPa)

These are the same as the earlier Coyote specs. See my initial post above for what happens at higher revs.

 

[FISHTAIL]

What type of oil pressure are you folks seeing when hot? My new 18 with about 200 miles on it reflect hot oil pressure of about 30PSI at speed and about 20 or less at idle. Not sure if I have a problem or not as I have been unable to find what normal pressures are for this vehicle. Only had it 2 days, so haven't had much opportunity to dig yet. but the low numbers concern me.

Gary

Mine is the same, and it makes zero noise, so I think your good. I only posted because the behavior was different than what I'm used to seeing and I wanted to make sure it was normal. I wasn't ever under the impression my engine had an issue as much as the interior gauge.

Could you put a 15-17 oil pan on your '18 if these composite oil pans keep giving issues?

I don't know. The 15-17 pans have a lower capacity (8 vs 10 qts) so I'd be hesitant to swap one unless we knew it was safe to do so. MMR makes a high capacity metal pan with baffles for racing so if this happens more than once I'll be pressing my case for that. I'd rather the dealer just fix it with an aftermarket part if this repeats than going through some lemon law nonsense over a leaky oil pan gasket.

The biggest bummer for this whole thing for me is they have to drop the whole front subframe to do this job, and I fear multiple return trips to get things back to how they should be. Car drives awesome right now, and I'd hate to lose that.

 

[DickR]

Don't blame the "pan" for a leak until the actual source of the leak is determined.

Regarding changing pans there is a lot of oil control engineering in that pan.

Per Ford Performance Tech Line the production 2018 5.0 composite pan is similar to the GT 350 pan in regard to oil control. https://performanceparts.ford.com/part/M-6675-M52

 

[glmarker]

Thanks guys for your responses. At least I know my pressure is normal. This 18 GT is SO MUCH DIFFERENT from my 14 V6. Like owning a completely different style and make of car. And I like everything I have found so far. :clap2:

Gary

 

[DickR]

Don't blame the "pan" for a leak until the actual source of the leak is determined.

Regarding changing pans there is a lot of oil control engineering in that pan.

Per Ford Performance Tech Line the production 2018 5.0 composite pan is similar to the GT 350 pan in regard to oil control. https://performanceparts.ford.com/part/M-6675-M52

Quoting myself

I read your leak post in another thread and did some google searching and see that composite pan leaks from Ford and other engines are common enough that they show up in Google. I have no idea how common these are relative to sales compared to modern metal pans.

Good luck!

 

[FISHTAIL]

Quoting myself

I read your leak post in another thread and did some google searching and see that composite pan leaks from Ford and other engines are common enough that they show up in Google. I have no idea how common these are relative to sales compared to modern metal pans.

Good luck!

Yeah, I was gonna say my blame of the pan was based on some prior knowledge of Ford having a multitude of issues with composite oil pans and leaking. Even the service writer at my local dealership wasn't surprised when I told him...just disappointed.

The sad part is my friend who owns a local speed shop warned me about the issues last week, and advised me to go get a few spare drain plugs because they apparently like to leak also. Then BAM. Leak. I blame him for jinxing me.

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