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Discussion Starter · #1 ·
Hello all,
When the engine is hot, and at idle, I sometimes have a light knock. It is only audible if you exit the vehicle, or if you are parked in a garage, next to a structure, etc. My oil pressure is right below 50 PSI at about 650 RPMs when this occurs. Cold start I get no knock and oil pressure is about 75 PSI till the rpms come down below 1000. If I give it slight gas to up the RPMs to 1000, the oil pressure is over 50 and knock is gone. I also have the light valvetrain noise that people mention at specific light loads and rpm ranges. That is also not really audible in the car unless at low speeds with AC and radio off. My oil level is fine and my consumption has not been bad (less than a qt per 1000 miles).

Is 40-50 PSI at warm idle normal for anyone else? Is this anything overly concerning? From a mechanical standpoint, it makes sense for me to be experiencing some of this. Now if I see the idle oil pressure decline over time, I will become concerned. My car has 3200 miles and I've only had it for about 1000 so am still discerning what the "normal" operating parameters are for this engine.

FWIW I plan to get my first oil change a week from tomorrow and of course discuss with Ford, check my oil filter for wear metal, and have everything documented.
 

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Not sure if this is the same thing but sometimes I notice a slight stumble at idle as opposed to a knock. It’s not a persistent thing but rather just comes and goes so I’m not concerned about it. Could this be the same thing?
 

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My only concern about oil pressure is when it's cold. I would be much more comfortable if it was closer to 60. Mine gets down into the 30s at idle when it's 110 in west Texas and I've just pulled off the Interstate. To put it in perspective my '67 gets down to about 15 at idle when the engine is hot in the summer and it has since it was new. The FE in my Starliner is about the same. The '67 and Starliner max oil pressure is about 60 psi when cold.

Just trivia from the past. :)
 

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You oil pressure numbers are similar to mine but if your concerned definitely take it to Ford and talk to them. Or you could give a Ford Performance a call. One of the other members might be able to give you a name and number a Ford Performance.
 

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Discussion Starter · #5 ·
I've talked to a couple folks who have reported close to 30 at hot idle, especially when oil level is closer to time to add. Thanks for the feedback. Maybe not west Texas, but I know all about those weeks where everyday is 100+ from living in Houston and San Antonio!
 

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Discussion Starter · #6 ·
The knock also comes and goes. When I pull into the garage in the evenings, it is hit or miss whether or not I'll hear it. They could be the same or have similar causes.
 

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I worked at auto parts stores for years and raced several cars and what I suggest is putting in a bottle of high mileage Slick 50 (with PTFE) or the new Classic Slick 50 (with PTFE) with each oil change because it will protect the engine at startup and/or with loss of oil like some of the GT350 issues with oil leaks.
 

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No, just NO, and please stop spamming these forums with that terrible advice.
Well I don't recall trying to sale anything to anyone. I guess you think I am giving some sort of advice about a top secret government product that they only know about because of the secret hidden aliens they have in Area 51.

Slick 50 coats the internal engine parts and if there is a loss of oil it would allow some time to pull over and add oil to take it to the dealership or allow you to pull over and get the car towed without there already being major damage to the engine. My boss (Advance auto parts) years ago was on his way home and he started hearing some light lifter noise from his truck engine. His oil pan had a gash in it from a rock hitting it and there was no oil left in the engine. Without the Slick 50 there would have been some major damage to the engine.
 

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Well I don't recall trying to sale anything to anyone. I guess you think I am giving some sort of advice about a top secret government product that they only know about because of the secret hidden aliens they have in Area 51.

Slick 50 coats the internal engine parts and if there is a loss of oil it would allow some time to pull over and add oil to take it to the dealership or allow you to pull over and get the car towed without there already being major damage to the engine.
No, it does none of those things. That is pure marketing BS.

My boss (Advance auto parts) years ago was on his way home and he started hearing some light lifter noise from his truck engine. His oil pan had a gash in it from a rock hitting it and there was no oil left in the engine. Without the Slick 50 there would have been some major damage to the engine.
I've heard of slant sixes being run to redline with no oil in them, and then being driven to the junkyard. The Slick 50 did NOTHING to save your boss's engine.
 

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I worked at auto parts stores for years and raced several cars and what I suggest is putting in a bottle of high mileage Slick 50 (with PTFE) or the new Classic Slick 50 (with PTFE) with each oil change because it will protect the engine at startup and/or with loss of oil like some of the GT350 issues with oil leaks.
Put any of those products in your engine and if Ford finds out your warranty goes bye bye.
 

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I hate to break it to all of the oil and additive experts on this forum, when you have a brand name "high mileage" oil it is their standard oil with cleaning additives added to it.

This is from a Mobil 1 high mileage synthetic oil ad...

Keep your older engines running like new with the help of High-Mileage Mobil 1 5W-20 Advanced Full-Synthetic Motor Oil. It is an advanced full-synthetic engine oil that is designed to provide exceptional wear protection, cleaning power and overall performance. This 5-qt motor oil bottle will support your car through oil change after oil change, helping to enhance and extend your engine's life. It does this by reducing deposits and sludge, protecting the parts in a high mileage engine. It also contains a seal conditioner to keep the engine seals in optimal condition and to prevent leaks. With excellent lubrication properties, Mobil 1 5W-20 Advanced Full Synthetic Motor Oil can be used in passenger cars, SUVs, light vans and trucks.

This is no different than adding something like Marvel Mystery Oil to your regular synthetic oil.

There is a difference between a brand name additive like Sea Foam and some off-brand gas station additive that claims it can fix for "broken" engine, etc...
 

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Do us a favor and go away. As you see most of us are not interested in your Slick 50. Or adding any additive just as the Shelby GT 350 supplement says. Theres enough having blown engines without escalating the chance of Ford not replacing it under warranty. Most of us use just what it says to use as far as oil and if theirs additives in that oil then were still covered cause thats the oil recommended to use. Troll your Slick 50 some where else.
 

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Do us a favor and go away. As you see most of us are not interested in your Slick 50. Or adding any additive just as the Shelby GT 350 supplement says. Theres enough having blown engines without escalating the chance of Ford not replacing it under warranty. Most of us use just what it says to use as far as oil and if theirs additives in that oil then were still covered cause thats the oil recommended to use. Troll your Slick 50 some where else.
All I have done is given a suggestion and/or opinion trying to help. I have never said or stated that anyone should do what I said. For there to be insults and spam/troll accusations is not warranted of me or anyone else just responding to a thread. I will leave.
 

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I hate to break it to all of the oil and additive experts on this forum, when you have a brand name "high mileage" oil it is their standard oil with cleaning additives added to it.

This is from a Mobil 1 high mileage synthetic oil ad...

Keep your older engines running like new with the help of High-Mileage Mobil 1 5W-20 Advanced Full-Synthetic Motor Oil. It is an advanced full-synthetic engine oil that is designed to provide exceptional wear protection, cleaning power and overall performance. This 5-qt motor oil bottle will support your car through oil change after oil change, helping to enhance and extend your engine's life. It does this by reducing deposits and sludge, protecting the parts in a high mileage engine. It also contains a seal conditioner to keep the engine seals in optimal condition and to prevent leaks. With excellent lubrication properties, Mobil 1 5W-20 Advanced Full Synthetic Motor Oil can be used in passenger cars, SUVs, light vans and trucks.

This is no different than adding something like Marvel Mystery Oil to your regular synthetic oil.
Who am I going to believe? A petrochemical engineer, or a guy who worked behind the counter at Advance Auto who doesn't know Plastigauge from Silly Putty?

There is a difference between a brand name additive like Sea Foam and some off-brand gas station additive that claims it can fix for "broken" engine, etc...
Red herring. We're talking about oil additives, not fuel additives.
 

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Discussion Starter · #17 ·
Well I apologize for creating a ruckus. I spoke with Ford about what I have posted and had a tech ride along. They are not concerned about any of it. I had my first oil change. It was clean with no metal and less than 0.5qt usage in 3500 miles so I am quite pleased. I would like to note that with after the oil change, my hot idle pressure is up 5-10 lbs and it seems to knock less at the range I described. I attribute it to clean oil and having that 0.5qt or so being replenished.

I have spoken with other folks whose hot idle oil pressure drops as their oil level declines. They replenish, pressure increases back. Sounds like a characteristic of the car to me. I can afford this car. I cannot afford to void a warranty on this car so I will NOT be using any products other than the recommended oil (or its equivalent for those amsoil fans ;) ).

Thank you to the senior members looking out.
 
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