Mobil 1 5w20 in ford v10 half oil gone in 3100 miles and 11 months.

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I have owned my f350 v10 since new. Change my mobil 1 5 w 20 once a year currently. Which is less than 5000 miles. Used to drive more and changed twice a year or three times a year. Never over about 5000 miles. Only mobil 1 oil filters.
So i just changed oil a couple days ago and only got out about 3 quarts of drain oil. It looked bad. And I know it was filled because i had just bought three of the 5 quart jugs.. and this year one was full and one had 4 quarts in it.
I see no smoke... smell nothing.. no drips under truck or on the ground. No oil in my coolant. No oil outside the engine..
So the lack of checking oil level was stupid. I never have added even a quarter quart so I got out of the habit checking oil level. I have been dealing with serious health issues as well.
Did I do much permanent damage ??

I plan on checking level monthly and looking for more loss. I saved the oil i took out and am thinking of sending for oil analysis now and in 6 months.
I today noticed I actually have the drain oil from last fall. I can see my service notes and know miles and nothing added.. and it was also mobil 1. 5 w 20 which i have used for 20 years.. no other oil ever in the truck..

I did have a stuck open thermostat from around christmas 2020 to middle april 2021 and the truck radiator was measured by me at around 130 degrees. So not a lot of heat in the cab. Could that have effected my oil consumption ??
So any ideas or thoughts would be appreciated.. i feel like an idiot.. i could have checked oil level every other month and avoided all this.

Would you just send in the oil sample from 2 days ago ?? Or also send in the used oil from 11 months ago...
I dont normally store old oil but i noticed it today in my garage..
Thanks. Scott in wisconsin
 

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If it's not seeping externally, it's either burning by getting past the rings or by running down the valve guides around worn/rotted valve stem seals, a quart ever 1500 miles wouldn't be noticeable in the exhaust in most cases. Whether running it 3 quarts low did any damage or not, only time will tell. Just keep up on checking the dipstick, maybe switch to a thicker oil and/or a high mileage oil.
 
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Higher age 2v modulars definitely suffer from the valve stem seals wearing out and letting oil past the valve stems. Also check the right head gasket, the early 5.4 and 6.8s will seep oil from the passenger side head gasket.

I ran mine down to 1 quart of oil in the pan when the oil cooler failed and pumped all of the oil into the coolant. The engine still runs fine at nearly 240k miles.
 

Quantico

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Have no puff of oil at startup like valve stem seals would show up as... i was plenty angry at myself not checking oil levels. I looked everywhere for any drips of oil. None found.. i live in a suburb with a 30 foot wide 120 foot long driveway. Have 2 garages. I see zero drops anywhere. I am a gearhead and engineer so i watch for that. I did manage to not check oil for 11 months and that was my failure. Glad the engine seems ok.. no valve or piston clatter. No oil light.. no low oil pressure on my guage... i just wish i had checked oil every 3 months.. the entire issue would have not happened...
I am going to change oil from now on at least twice a year.. and check oil level monthly. I am putting in phone alerts.. and because i am an engineer i am going to make a form to track my tests.
 
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if there's no small puff at startup from oil pooling in the cylinders than maybe it's the pcv valve. I'd clean or change it first and if it doesn't help as much as you'd like you can for sure run a much thicker oil in that series of engines.

A 20 grade is a bit thin anyway. Really doubt the engine has sludge either with that time and mile intervals but what the heck a seafoam flush and 3-5 hours of soft driving wouldn't hurt anything.

I used to put 10/15w-40 in my 97 f150 since it was brand new instead of that diet 20 grade and it got to around 178k if i recall without burning until it got stolen in mexico in 09. Did clean the pcv as preventative maintenance since my friend told me to clean it every 50k tops. Used a can of brake cleaner.
 

Quantico

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Good advice thanks.. i will be upping my checking and go to twice a year. I am going to send in oil sample or samples. And more samples in 6 months.

Never ever thought of the PVC valve.. i can clean or replace it as its 20 years old.
My truck was driven 15 k a year when new. Then I bought a bmw collector car.. and 8 or ten years ago got my moms mercury grand marquis when my mom died.. also my girlfriend has several vehicles so I have driven her bmw X5 often.. she buys a new one every 3 years so a lot of the time I use that..
So if your curious why my truck is getting used 3000 miles a year its having a lot of cars to drive..
My bmw gets stored for winters with new oil every fall before storage... and I use heavier summer weight oil in in because the old E36 engines need thicker oil for temps over 75 degrees according to the bmw owners and service manuals.
 
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Good advice thanks.. i will be upping my checking and go to twice a year. I am going to send in oil sample or samples. And more samples in 6 months.

Never ever thought of the PVC valve.. i can clean or replace it as its 20 years old.
My truck was driven 15 k a year when new. Then I bought a bmw collector car.. and 8 or ten years ago got my moms mercury grand marquis when my mom died.. also my girlfriend has several vehicles so I have driven her bmw X5 often.. she buys a new one every 3 years so a lot of the time I use that..
So if your curious why my truck is getting used 3000 miles a year its having a lot of cars to drive..
My bmw gets stored for winters with new oil every fall before storage... and I use heavier summer weight oil in in because the old E36 engines need thicker oil for temps over 75 degrees according to the bmw owners and service manuals.
i don't really think more than one oil analysis is necessary. Just a basic one without TBN just to see how wear metals are doing and if they're fine i wouldn't do another.

Also i believe ford doesn't even spec the v10 for a 20 grade and if they did you might've not been notified about the change. Says only a 30 grade and that it should meet a particular ford wss spec but that's not too important just a nice have. I'd at least switch to a 5w-30 grade as it says the v10 should only have or a 40 better yet.

A 50 grade doesn't provide additional protection to be worth the added minimal fuel usage unless it was a real burner but it isn't so a 40 is more than adequate.

Wisconsin isn't cold from what I've heard so you can use a 15w-40 like i do since it doesn't gets cold down here. i just used a 5w-40 in my trucks this time around cause i got it pretty cheap but it's long gone and will be going back to supertech 15w-40. Meets the fairly stringent ford wss and volvo vds 4.5 spec so that's all one needs to know if its gold or not. I'm sure your engine would like. i ran 10/15w-40 in my 5.4 to just south of 200k since new without a single issue I doubt yours will have either.
 
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One of the reasons why many manufacturers suggest 6 months OCIs even if not exceeding mileage limit.
 
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OP, in 2015 Ford changed the spec for the 6.8l to 5w-30, that’s what I’ve been running in mine. Oil consumption is almost nonexistent over a 5k interval. Search for past posts about this subject here on BITOG.
 
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OP, in 2015 Ford changed the spec for the 6.8l to 5w-30, that’s what I’ve been running in mine. Oil consumption is almost nonexistent over a 5k interval. Search for past posts about this subject here on BITOG.
I had a 15-16 V-10 in a 25' motorhome. Ran Mobil 1 5-20 and it didn't use any oil in 5k miles. Engine ran great, just required a lot of gas.
 

Quantico

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i don't really think more than one oil analysis is necessary. Just a basic one without TBN just to see how wear metals are doing and if they're fine i wouldn't do another.

Also i believe ford doesn't even spec the v10 for a 20 grade and if they did you might've not been notified about the change. Says only a 30 grade and that it should meet a particular ford wss spec but that's not too important just a nice have. I'd at least switch to a 5w-30 grade as it says the v10 should only have or a 40 better yet.

A 50 grade doesn't provide additional protection to be worth the added minimal fuel usage unless it was a real burner but it isn't so a 40 is more than adequate.

Wisconsin isn't cold from what I've heard so you can use a 15w-40 like i do since it doesn't gets cold down here. i just used a 5w-40 in my trucks this time around cause i got it pretty cheap but it's long gone and will be going back to supertech 15w-40. Meets the fairly stringent ford wss and volvo vds 4.5 spec so that's all one needs to know if its gold or not. I'm sure your engine would like. i ran 10/15w-40 in my 5.4 to just south of 200k since new without a single issue I doubt yours will have either.
Thanks to several of you. I did not know ford changed its spec for my triton v10. I did just buy several more jugs of 5 w 20. But i can change to 5 w 30 in the future.
Let me ask a dumb question.. ?? I run 15 w 50 for my older e36 bmw . Can I mix half and half from 15 w 50 mobil one to make closer to the 5 w 30 ? I also have jugs of 5 w 30 mobil one i use in the bmw in winter just in case the car has to run a bit.
Fyi I went to yearly oil changes not to save money. Just to limit my trips under the car and truck with a bad knee. But I can revert to twice a year without too much trouble.
 
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Check/change your PCV before you do anything drastic. I'm not into "mixing" different brands/grades of motor oil so no advice there.
 

blupupher

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My '02 F150 with the 5.4 goes through a qt every 1,200 miles or so, no smoke, no leaks, PCV replaced with OEM twice in the past 7 years since I got it.
It is a replacement motor from an '03 that had ~120,000 miles at the time of the swap.
Has ~155,000 or so on the motor now. Oil use has been consistent since the swap.

I have only used xw-20 synthetics, and noticed no difference between brands.
I may go to a 5w-30 once my stash of 5w-20 is gone.
 
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I run 5.4 and the V10 ford's in a commercial environment they always used oil and always ran 5/30 syn with motor craft filter. I highly doubt any damage was done just check your oil level every Saturday morning to check for a trend
 

Quantico

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Sent in my oil yesterday to blackstone. Just bought a new pcv .. will install asap and change the air filter as well
 

Quantico

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UPDATE.. not super interesting but my truck in first gear has always rolled a bit on my garage driveway slope. Its not a huge angle. And the truck has done this as soon as I put in mobil 1 5w20.
Truck rolled about 10 to 12 feet from where I parked it last night in gear. No park brake on..

Again this is how the truck has always acted with hot 5 w 20 oil..
But it was not further than usual.
And my clutch is almost new. Only 30 k miles on it since a shop thought my clutch was bad at 80 k miles. They pulled the clutch and measured it as 10 percent worn. Opps
 
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