Reason For XS Oil Usage?

CANTWN4LSN

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Not bitchin'. Some cars use oil and some don't, mine being in the former group. Haven't seen anything yet on exactly what the most common reason is and I suspect there probably is just one for 90% of cases. Lots of speculation but has anyone addressed this on their car and fixed it? Wondering if worth trying to resolve or just resign myself to carrying four quarts of oil in the trunk on any extended 6-7000 mile road trip I take until I die (which is probably the least expensive answer).

 

Socalrugger

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I use about 0.5-1 qt every 500 miles or so…..aside from that, I’ve had no issues and the car performs great so I just keep a few quarts in the trunk
 

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I'd be surprised if this thread turns into much more than the usual case of people all chiming in to report their oil usage. I'm not sure how you'd definitively determine this, but there's been speculation that much of it has to do with oil leakage past the valve seals.
 
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CANTWN4LSN

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It doesn't seem as many Gen 2 cars after 2018 are as apt to use oil as earlier ones so wonder if anyone knows if they changed something regarding the valve seals, if that was the problem, on the newer models? Wouldn't that be a relatively inexpensive fix?
Agree with your caveat, don't want to turn this into a "my car doesn't use any oil thread", just wondering if someone has figured this out or there is a relatively inexpensive solution.
 
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CANTWN4LSN

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Also if they put the same valve seals in every car, doesn't make sense why one uses more oil than another from the get go rather than as a function of wear over time.
 


Andy13186

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lol how often do you take 6-7k mile road trips? adding oil is easy, and you probably wont burn nearly as much if you arent revving the car out often. You should change your oil every 3k too anyway
 

Demonic

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It doesn't seem as many Gen 2 cars after 2018 are as apt to use oil as earlier ones so wonder if anyone knows if they changed something regarding the valve seals, if that was the problem, on the newer models? Wouldn't that be a relatively inexpensive fix?
Agree with your caveat, don't want to turn this into a "my car doesn't use any oil thread", just wondering if someone has figured this out or there is a relatively inexpensive solution.
Part numbers for many parts in the engine change over years, as with most engines. This is why the 'gen' can be a bit of a misnomer, since parts and part numbers will continually change based on things like supplier contracts and availability, or minor part revisions, changes in materials, etc. If you tried to have your engine rebuilt every time there was a minor part revision it would never spend any time in the car. I believe there have been changes in part number for valve seals, but someone else would have to confirm. Now the question of why not replace seals in older engines becomes a case of why fix what isn't broken. If the car actually is burning more oil because the valve seals allow more leak-by, then that isn't necessarily a problem. I believe there was a Ford document circulated at one point stating that after more analysis many engines that were replaced for oil consumption alone were actually fine. Now in the case of the 2020's with the unreleased chain tensioners we're talking about a very different situation. I should add the caveat that I'm the opposite of an engine expert.
 
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CANTWN4LSN

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Actually bought the car to tour so take a long trip twice a year in U.S. and Canada, altho Covid put brakes on that recently.
Appreciate the practical aspect, just add a quart every 1500 miles and live with it. @Unhandled Exception has been doing it for 30k more miles than I have. But there is an intellectual curiosity about a solvable mechanical "problem" and just wondered if anyone had solved it.
Hard to wrap an OCD head around it's okay to burn that much oil, and without wear and tear why one car does and another built the same way with same components doesn't. It is what it is remains the answer I guess.
 

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Not bitchin'. Some cars use oil and some don't, mine being in the former group. Haven't seen anything yet on exactly what the most common reason is and I suspect there probably is just one for 90% of cases. Lots of speculation but has anyone addressed this on their car and fixed it? Wondering if worth trying to resolve or just resign myself to carrying four quarts of oil in the trunk on any extended 6-7000 mile road trip I take until I die (which is probably the least expensive answer).
My favorite possible reasons:
  • Piston ring was accidentally tweaked during engine assembly process
  • High RPM low load operation
  • Car is babied too much and the cylinder walls are glazed
Less favorite but possible
  • Valve guide(s) a little loose
  • Issue with a valve seal

If you are in warranty, try to get it fixed by Ford for free. The cost of repair obviously depends on the problem. I'm not sure whether the PTWA cylinder bores can be honed or whether you would have to go straight to sleeves ($$). Valves are a lot cheaper to fix if that's the source of the issue.

Personally I would choose sleeving your block over buying another throwaway block with the chintsy PTWA liners. I thought a lot about all this when I still owned a GT350 and I became reluctant to sign up for any of it. I can do a lot of the work, but do I want to spend the time is the question.
 

Angrey

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If Ford knows, they ain't saying. It's not jailhouse lawyering to assume they don't want to expose themselves to class action suit or recall.

It's either valve seals or blow by. Blow by could be caused by a few things, but I can tell you this.

High performance cars generally need to be driven spiritedly.

They also can't be driven like a typical daily driver mini-van, meaning it's not just a car you jump in and go when the motor is cold.

I'm pretty OCD about letting the car warm to at least 120F coolant temp (that's when the idle drops) and then not flogging it until it reaches full operating temps.

Then, on the flip side, you have to give the car the business every so often (I mean, the FULL business, as in redline rips from 1-4 or 1-5) to keep rings properly mated and cylinder walls free and clear.

There's no doubt in my mind that the car experiences blowby when the pistons are cold and slapping around at off angle, so I try to keep that at a minimum and only either idle or creep it until they've fully expanded.

It's a bit obscure, but when I rebuilt my motor and had the heads done, I had purchased a set of new valve seals from MMR (which I'm fairly certain are just rebranded FRPP seals) and for whatever reason, MPR (who did my heads) wanted to use a different set/spec. So that could be just their preference or it could be there's problem with the FRPP valve seals. I dunno.
 

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IMHO oil consumption has nothing to do with Gen 2 or Gen 1. I know somewhere in time the ring package changed and that was well before 19. My 16 used minimal oil as does my 19.
 

passwords

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IMHO oil consumption has nothing to do with Gen 2 or Gen 1. I know somewhere in time the ring package changed and that was well before 19. My 16 used minimal oil as does my 19.
If I recall correctly when the voodoo was introduced, along with the PWTA cylinder walls, Ford was proud about the low tension oil control rings. The only way to manage 12:1 compression is with the oil squirters sending oil to the bottom side of the piston to keep it cool enough to avoid detonation. This is complete speculation on my part, I readily admit that. But low tension oil control rings and oil squirters sending oil to the bottom of the piston seems to me like it could be a significant contributing factor to oil consumption.

I have a ‘19 R and it does not use any measurable oil. I personally believe that has more to do with the changes in piston rings (specifically the oil control rings) than the “gen2” block or valve seals.
 

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piston ring to wall & valve guide clearance are the biggest culprits for internal oil consumption
 

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If Ford knows, they ain't saying. It's not jailhouse lawyering to assume they don't want to expose themselves to class action suit or recall.

It's either valve seals or blow by. Blow by could be caused by a few things, but I can tell you this.

High performance cars generally need to be driven spiritedly.

They also can't be driven like a typical daily driver mini-van, meaning it's not just a car you jump in and go when the motor is cold.

I'm pretty OCD about letting the car warm to at least 120F coolant temp (that's when the idle drops) and then not flogging it until it reaches full operating temps.

Then, on the flip side, you have to give the car the business every so often (I mean, the FULL business, as in redline rips from 1-4 or 1-5) to keep rings properly mated and cylinder walls free and clear.

There's no doubt in my mind that the car experiences blowby when the pistons are cold and slapping around at off angle, so I try to keep that at a minimum and only either idle or creep it until they've fully expanded.

It's a bit obscure, but when I rebuilt my motor and had the heads done, I had purchased a set of new valve seals from MMR (which I'm fairly certain are just rebranded FRPP seals) and for whatever reason, MPR (who did my heads) wanted to use a different set/spec. So that could be just their preference or it could be there's problem with the FRPP valve seals. I dunno.
when were your heads done by MPR? Tim had to use different seals on mine because I was having issues with them leaking
 

Postal Bob

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I always believed excess oil consumption was due to not properly breaking in the engine. If done right, the rings will seat properly, and not have excess oil consumption. The engine during break in needs to have acceleration, and deceleration under load to properly seat the rings. And this with the Ford recommendation of just going easy the first 100 miles, I feel is off.
I was very easy on my car the first several hundred miles. I drove it like an old man during that time, with constant deceleration while in gear. And I feel it paid off. When I was past 1K miles, is when I started to open it up. I now routinely drive it in the 6K-8K rpm range. And at 5500 miles, I'm lucky if I had to add even 1/2 qt of oil. Compare that with those who drove it like they stole it from day one, and go through 1 qt oil every 500-1000 miles.
 

 
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