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

Sounds like low compression……you are leaving it in gear on a hill and expecting it not to roll. I expect you’re using 1st?
Its been doing that since I switched from ford oil in 2001. Same house. Not a huge slope. So I dont think my engine has had low compression 116 k miles. Its never used oil until the last 11 months 3000 miles ago..

By the way looked at the tech serv bulletins. Ford changed to 3 w 30 almost 19 years ago. Then went back to the orig factory recomendation of 5w20 maybe 17 or 18 years ago.

So the 5 w 20 is current correct spec and correct for the tsb stuff
 
Got back my oil analysis today. Looks bad to me but I am no expert at understanding how bad my engine may be.
 

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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


So it’s the 5w20 that makes it roll on a sloped driveway when parked?

Why don’t you use the parking brake?
 
So it’s the 5w20 that makes it roll on a sloped driveway when parked?

Why don’t you use the parking brake?
No big reason. I just found it interesting that the switch to mobil 1 5 w 20 oil was thin enough that my truck could very very slowly roll a few feet .. but it did not do it with conventional oil.
My driveway is 125 feet.. no other cars in front of my truck. And when it chooses to slowly roll it a few feet before the engine cools and it cant roll.
I just always found the situation interesting as an example of great oil.
Everything has to be just right. Pretty hot weather.. tires to near 80 psi. Never tried leaving it in reverse..
I have sat in the truck a minute and left the brake on.. and the engine cooling the first few minutes seems to stop the slow engine movement.
I find it interesting this has gone on about the same for 20 years..
 
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UPDATE END OF YEAR..

i have been checking oil with no loss until this week at just over 500 miles since oil change. DOWN 3/4 quart. So i filled it up to the top again. I will be checking it every 200 miles.

So the rate of useage is about a quart every 700 miles. Not ideal but I can keep at that.

I got advise from several people to :
1 check pcv system and valve. And its fine.. no problem.

2. Switch to a thicker oil from mobil 1 5 w 20 to something thicker.

That could be 5 w 30. Or 10 w 30. or I could mix in 2 or 3 quarts of mobil 1. 15w50 that I use in my bmw. Opinions on what to try to see if I could get less oil consumption??
 
Ideally you probably should take it to a mechanic you trust and have them look into it, it sounds like you have very low compression if the truck rolls in gear and the UOA you received seems to agree with that I doubt a thicker oil will fix your issue
 
Ideally you probably should take it to a mechanic you trust and have them look into it, it sounds like you have very low compression if the truck rolls in gear and the UOA you received seems to agree with that I doubt a thicker oil will fix your issue
I could take it to a mechanic. But I am not going to replace or pull and rebuild an engine on a truck that has low value.
The rolling slightly when hot and on a hill and using mobil 1 5w20 has been going on for 116 thousand miles over 20 years.. since new.
So the truck brand new did not roll when hot. But when i switched to mobil 1 at less then 6000 miles it started doing that. So I think the compression could be low now. But not because it rolls when hot. That has been since brand new.
 
The cost of putting in a rebuilt engine would be 6000 to 7500 dollars. I think the truck current value is about 4000 dollars.

In the last 2 years the truck got a new clutch..exhaust..steering box..front end...all brakes..tires.. air conditioning. So that was allready a huge mistake. About 5500 of repairs in a 4000 dollar to 5000 truck. If it was not rusty from being in wisconsin and salt. It might be worth it. But I dont see the value in a repaired engine. Pulling out the engine and repairs would be a huge deal.
Anyone here interested in buying a 20 year old truck with some rusty wheel wells for any amount that would make sense to put way more money in it ??
 
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