The Ford Barn

TomC750 · 01-11-2025, 08:33 PM

I just ran across an official Ford chart for my '41 that lists oil viscosity for different temperature ranges. I was surprised that 40 weight was listed for summer, when I had planned on 30 weight. Perhaps I should consider 10-40? Typo in title, Supposed to say "Engine oil!"
What say you folks?

cas3 · 01-11-2025, 11:37 PM

is it a new engine? Oils are way better today than back in the flathead era.
Oils can also be a wild topic here, but I think most folks are using modern 10-30 or 15-40 depending on climate and use. Next.....

V8 Bob · 01-12-2025, 09:14 AM

Quote:

Originally Posted by TomC750

I just ran across an official Ford chart for my '41 that lists oil viscosity for different temperature ranges. I was surprised that 40 weight was listed for summer, when I had planned on 30 weight. Perhaps I should consider 10-40? Typo in title, Supposed to say "Engine oil!"
What say you folks?

IMO, you should NOT run a heavier weight oil than your engine really needs, and this requires an accurate oil pressure gauge to know for sure. Both my flatheads, one stock I've owned for 24+ years with no known previous history, and one fresh and highly modified use 10W30, resulting in very good low and high RPM oil pressure. Heavier-than-needed oil viscosity is not only harder on the oil pump and related gearing, but takes longer to circulate to critical areas especially in colder climates.
I would forget about what oil was "listed" 80+ years ago and simply use a quality modern "detergent" oil with the appropriate weight for your engine and usage.

pistonbroke · 01-12-2025, 09:39 AM

I second V8Bob. I sheard the pin on the oil pump gear in my lincioln V12 running 20-50. Tim

TomC750 · 01-12-2025, 11:48 AM

Quote:

Originally Posted by cas3

is it a new engine? Oils are way better today than back in the flathead era.
Oils can also be a wild topic here, but I think most folks are using modern 10-30 or 15-40 depending on climate and use. Next.....

No, not a new engine, mileage is unknown. Runs like new one. Oil pressure with stock gauge at hot idle is just off the peg, at 30 MPH it is about in the middle which would be 20 psi. I do need to check with a mechanical gauge.
Thanks for the helpful response.

TomC750 · 01-12-2025, 11:58 AM

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Quote:

Originally Posted by V8 Bob

IMO, you should NOT run a heavier weight oil than your engine really needs, and this requires an accurate oil pressure gauge to know for sure. Both my flatheads, one stock I've owned for 24+ years with no known previous history, and one fresh and highly modified use 10W30, resulting in very good low and high RPM oil pressure. Heavier-than-needed oil viscosity is not only harder on the oil pump and related gearing, but takes longer to circulate to critical areas especially in colder climates.
I would forget about what oil was "listed" 80+ years ago and simply use a quality modern "detergent" oil with the appropriate weight for your engine and usage.

I am running straight 30 weight presently. Although it runs sweet and smooth with zero smoke, I was disappointed when I drained the old oil a good bit of sludge came out. For a supposedly restored car the lack of maintenance was disappointing. I will get a good gauge on it.
Thank You!

tubman · 01-12-2025, 12:34 PM

Sludge coming out is not a bad thing. If anything, I would run detergent oil and do frequent changes. You may be able to clean more crap out of it. Although I agree with "V8 Bob" about running the thinnest oil practicable, I would go with the 10W-40 for an unknown used engine. I wouldn't worry about the sludge clogging up the engine, as detergent oil is designed to keep it in suspension. Just change it more frequently.

The previous owner may have run non-detergent oil, which is not a good idea.

ThirstyThirty · 01-12-2025, 02:03 PM

Quote:

Originally Posted by TomC750

I just ran across an official Ford chart for my '41 that lists oil viscosity for different temperature ranges. I was surprised that 40 weight was listed for summer, when I had planned on 30 weight. Perhaps I should consider 10-40? Typo in title, Supposed to say "Engine oil!"
What say you folks?

Read it in Listing. Read it in thread!...

both times read to me: Engine Oil!! lol

maybe i need glasses!

Kube · 01-12-2025, 02:53 PM

Quote:

Originally Posted by ThirstyThirty

Read it in Listing. Read it in thread!...

both times read to me: Engine Oil!! lol

maybe i need glasses!

You do...

TomC750 · 01-12-2025, 09:06 PM

[QUOTE=tubman;2361877]Sludge coming out is not a bad thing. If anything, I would run detergent oil and do frequent changes. You may be able to clean more crap out of it. Although I agree with "V8 Bob" about running the thinnest oil practicable, I would go with the 10W-40 for an unknown used engine. I wouldn't worry about the sludge clogging up the engine, as detergent oil is designed to keep it in suspension. Just change it more frequently.

The previous owner may have run non-detergent oil, which is not a good idea.[/QUOTE
]I know. I have heard the following more times than I care to mainly referring to Model A's: They were originally designed to use non detergent oil or some similar statement or even marketed as the right oil for a vintage car. Boy oh boy...
And thanks for your advice. I will go with it.

flatjack9 · 01-12-2025, 09:35 PM

I have run 10w30 since I built my engine some 30 years ago. Usually whatever was on sale. Probably at least 70,000 miles on the engine. Had occasion to tear my engine down and it is as clean inside as when I built it. I credit modern oil, 180* thermostats and full flow oil filter. There was absolutely no wear on the crank, like new bearings, no ridge in the bores.

Drbrown · 01-14-2025, 10:46 AM

I also use 10w30 detergent - usually Penn State and include a quart to a half quart of Marvel Mystery Oil (MMO) with the change. Been using MMO since the 1950's. When purchased, this '47 had a sticky valve and it seems the MMO helped free it up. Oddly, my '47 has no oil filter but I change the oil every 1000 miles and it drains out quite clean. I use 165 thermostats but the engine runs at about 175 to 180 by itself.

01-11-2025, 08:33 PM	#1
TomC750 Senior Member Join Date: Dec 2024 Location: Eastern Tennessee Posts: 305	Engie oil I just ran across an official Ford chart for my '41 that lists oil viscosity for different temperature ranges. I was surprised that 40 weight was listed for summer, when I had planned on 30 weight. Perhaps I should consider 10-40? Typo in title, Supposed to say "Engine oil!" What say you folks? __________________ TomC750 1949 8NV8 Ford tractor 1930 1 Ton White 1941 Mercury Sedan Coupe Last edited by TomC750; 01-11-2025 at 09:01 PM.

01-11-2025, 11:37 PM	#2
cas3 Senior Member Join Date: Jan 2011 Location: Beverly Kansas Posts: 5,558	Re: Engie oil is it a new engine? Oils are way better today than back in the flathead era. Oils can also be a wild topic here, but I think most folks are using modern 10-30 or 15-40 depending on climate and use. Next.....

01-12-2025, 09:39 AM	#4
pistonbroke Senior Member Join Date: Feb 2021 Location: Perry Mo. Posts: 838	Re: Engie oil I second V8Bob. I sheard the pin on the oil pump gear in my lincioln V12 running 20-50. Tim

01-12-2025, 12:34 PM	#7
tubman Senior Member Join Date: Dec 2013 Location: Minnesota, Florida Keys Posts: 12,139	Re: Engie oil Sludge coming out is not a bad thing. If anything, I would run detergent oil and do frequent changes. You may be able to clean more crap out of it. Although I agree with "V8 Bob" about running the thinnest oil practicable, I would go with the 10W-40 for an unknown used engine. I wouldn't worry about the sludge clogging up the engine, as detergent oil is designed to keep it in suspension. Just change it more frequently. The previous owner may have run non-detergent oil, which is not a good idea.

01-12-2025, 09:06 PM	#10
TomC750 Senior Member Join Date: Dec 2024 Location: Eastern Tennessee Posts: 305	Re: Engie oil [QUOTE=tubman;2361877]Sludge coming out is not a bad thing. If anything, I would run detergent oil and do frequent changes. You may be able to clean more crap out of it. Although I agree with "V8 Bob" about running the thinnest oil practicable, I would go with the 10W-40 for an unknown used engine. I wouldn't worry about the sludge clogging up the engine, as detergent oil is designed to keep it in suspension. Just change it more frequently. The previous owner may have run non-detergent oil, which is not a good idea.[/QUOTE ]I know. I have heard the following more times than I care to mainly referring to Model A's: They were originally designed to use non detergent oil or some similar statement or even marketed as the right oil for a vintage car. Boy oh boy... And thanks for your advice. I will go with it. __________________ TomC750 1949 8NV8 Ford tractor 1930 1 Ton White 1941 Mercury Sedan Coupe Last edited by TomC750; 01-12-2025 at 09:10 PM. Reason: addition

01-12-2025, 09:35 PM	#11
flatjack9 Senior Member Join Date: May 2010 Location: Oshkosh, Wi Posts: 4,608	Re: Engie oil I have run 10w30 since I built my engine some 30 years ago. Usually whatever was on sale. Probably at least 70,000 miles on the engine. Had occasion to tear my engine down and it is as clean inside as when I built it. I credit modern oil, 180* thermostats and full flow oil filter. There was absolutely no wear on the crank, like new bearings, no ridge in the bores.

01-14-2025, 10:46 AM	#12
Drbrown Senior Member Join Date: Oct 2013 Location: Glens Falls NY Posts: 1,403	Re: Engie oil I also use 10w30 detergent - usually Penn State and include a quart to a half quart of Marvel Mystery Oil (MMO) with the change. Been using MMO since the 1950's. When purchased, this '47 had a sticky valve and it seems the MMO helped free it up. Oddly, my '47 has no oil filter but I change the oil every 1000 miles and it drains out quite clean. I use 165 thermostats but the engine runs at about 175 to 180 by itself.