Ford v10 consuming Mobil 1 5w20 Recomendations of weight? Would 5w-30 be better?

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A few months ago my ford f350 used 3 of 6 quarts. In 3000 miles ...but over a year...

Started over with new 5 w 20 mobil 1 and consumed 3/4 qt in 550 miles.. so i want to try a heavier thicker oil.

So. 5 w 30 would protect more but 5 weight is 5 weight.

So maybe 10 w 30 mobil 1 ??

Or I have lots of 15 w 50 mobil 1 I could mix with 10 w 30 maybe ?? Maybe 2 or 3 quarts of the 15 w 50 ??
What is your opinion ?
 
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That engine could easily use a 40 grade without it being thick. Have you tried anything to reduce consumption. I believe many of us gave suggestions in the previous posts. Has nothing worked? if no id get supertech diesel as its cheap and will last long enough. That engine burns too much to have anything full syn.

What the coldest temp it starts up at?
 
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Have someone slightly power brake it with the e-brake set while you watch the oil fill with cap removed. If you see smoke, then you've got a lot of blow by from poor ring sealing. Replace the PCV valve and look for vacuum leaks which could affect the PCV function.

With that much consumption, I'd probably just use 15w40 and call it good. Tons of fleet maintained mod motors went a long, long time with nothing but 15w40 diesel oil.
 

Quantico

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Have someone slightly power brake it with the e-brake set while you watch the oil fill with cap removed. If you see smoke, then you've got a lot of blow by from poor ring sealing. Replace the PCV valve and look for vacuum leaks which could affect the PCV function.

With that much consumption, I'd probably just use 15w40 and call it good. Tons of fleet maintained mod motors went a long, long time with nothing but 15w40 diesel oil.
I did rev the engine. I see no blow by coming out the oil fill cap when removed. Using a quart every 700 miles is not that visable.

I live in wisconsin. Cold start temps are about 30 to 40 degrees currently. If we get a cold snap that could become 15 degrees.

Twice in the last 40 years I worked outside at - 26 degrees F. Not wind chill crap. Actual air temp. But those are abnormal for wisconsin / milwaukee weather..

Generally 25 to 35 are typical winter temps.
 

Quantico

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I did rev the engine. I see no blow by coming out the oil fill cap when removed. Using a quart every 700 miles is not that visable.

I live in wisconsin. Cold start temps are about 30 to 40 degrees currently. If we get a cold snap that could become 15 degrees.

Twice in the last 40 years I worked outside at - 26 degrees F. Not wind chill crap. Actual air temp. But those are abnormal for wisconsin / milwaukee weather..

Generally 25 to 35 are typical winter temps.
My pcv valve is perfect. No reason to change a part I just tested.
 

Astro14

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"Used 3 of 6 quarts" implies that you never added oil during that time.

That's a problem. If you don't top it off, and it gets a couple quarts low, the consumption rate will go up.

The first number has nothing to do with consumption, that's how the oil flows when it's cold, and thousands of times thicker than when it's hot.

Get over the first number (in some product lines, a 0W30 is thicker at operating temperature than a 5W30 or a 10W30) and start looking at the second number to reduce consumption past worn rings, worn valve guides, or bad valve stem seals, whatever problem it is that this truck engine has. You say it's not PCV, and you say it's not leaking, so it has to be one of those to get from sump out the exhaust pipe.

Because you're in Wisconsin, and it's cold, I would start with a 5W40. Rotella T6 would be my recommendation. Inexpensive, synthetic, big step up in viscosity. Buy some extra, check the level each fill up and top off when needed, before it gets to the "add" line on the dispstick.
 

Quantico

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"Used 3 of 6 quarts" implies that you never added oil during that time.

That's a problem. If you don't top it off, and it gets a couple quarts low, the consumption rate will go up.

The first number has nothing to do with consumption, that's how the oil flows when it's cold, and thousands of times thicker than when it's hot.

Get over the first number (in some product lines, a 0W30 is thicker at operating temperature than a 5W30 or a 10W30) and start looking at the second number to reduce consumption past worn rings, worn valve guides, or bad valve stem seals, whatever problem it is that this truck engine has. You say it's not PCV, and you say it's not leaking, so it has to be one of those to get from sump out the exhaust pipe.

Because you're in Wisconsin, and it's cold, I would start with a 5W40. Rotella T6 would be my recommendation. Inexpensive, synthetic, big step up in viscosity. Buy some extra, check the level each fill up and top off when needed, before it gets to the "add" line on the dispstick.
I think thats great advice. Thanks ...will do that as soon as i can get under it in the cold..

I used the truck 3000 miles in 11 months.. and did not check it or add because in 20 years it never used even 1/4 quart in 5000 or 6000 mile runs between changes.

I had and still have a life changing injury... and have not felt well enough to do the normal stuff.
 

dnewton3

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OP - I realize you've checked the PCV valve; change it anyway. They are cheap and quick to change, and the very smallest of leak on that component can affect oil consumption. What you think is good may well not be so.

If you change the PCV and still have oil consumption, then the second most likley thing is the valve stem seals. Now, not so cheap in terms of cost and time.

I saw your other thread; there's some Fe wear going on for sure. Not sure if you've got a more recent UOA to show us?
 
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One of the places I used to work at had a shop truck F450 with flatbed, and same V10 engine. Shop owner got tired of adding oil every week, so he finally had mechanic replace the valve cover gasket, despite not seeing any leaks. Replaced, and turns out it was leaking oil from the very back of the valve covers, onto the bell housing, and rest of transmission and driveline. It was hard to notice as engine looked dry otherwise.
 

Astro14

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I'm sorry to hear of your injury. Makes it hard to do any mechanical diagnosis, much less work.

In all honesty, if this were mine, I might not even fix it. I ran an old Toyota 4 Runner for over 100,000 miles with a rear main seal leak.

It leaked out about a quart every 1,500 miles, or it burned and leaked it, I was never certain.

Either way, the time, cost and effort of adding a quart every month or two was way less than the time, cost and effort of pulling the engine on a 4WD to fix a rear main seal.

PCV valve is cheap and easy. Throw a new one in when you change the oil.
 

Quantico

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I replaced the ford oem pcv valve at 75 k when i did plugs. So the pcv valve has about 40 k miles. I just pulled it and cleaned it. It seals well in one direction..cleaned it with carb clean and rinsed w areo kroil spray oil then cleaned with air compressor..
The whole setup was 60 bucks from ford. But its good. I do have a spare valve i could install. But its silly at some point to keep replacing a part that is tested and working that has 40 k miles on it.
 

Quantico

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OP - I realize you've checked the PCV valve; change it anyway. They are cheap and quick to change, and the very smallest of leak on that component can affect oil consumption. What you think is good may well not be so.

If you change the PCV and still have oil consumption, then the second most likley thing is the valve stem seals. Now, not so cheap in terms of cost and time.

I saw your other thread; there's some Fe wear going on for sure. Not sure if you've got a more recent UOA to show us?
Dont have a new oil analysis yet.. blackstone told me to go to 800 miles before the analysis was usefull. I am at 550 miles so soon i will change oil and do another analysis..
 
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