What weight oil should I use - Brand?

[jplutz]

Greetings & Salutations,
I just got this beauty back on the road after rebuilding 95% of the brake system. When I changed the oil & filter, I put in 10w30 cuz that's what I had. At idle, cold, the pressure is great, as per photo. And driving around the neighborhood it still stays good. But..The other day in 90deg heat I took her out on the local highway for a 2 mile round trip drive, and by the time I was returning home the pressure was in the pits, unless I reved the engine and raced down the road.
I realize that I screwed up with the oil. What weight should be used? I have a gallon jug of 5w40. Is that ok, or is the 5 side too lite? Is there a brand that is best? BTW, the engine did not overheat, the temp was steady.
Thanking you in advance, I remain
Yours Truly, JP Lutz
ps. I have dog dish on one side & baby moons on the other, and I paid thru the nose for the patina.. ha, ha!!

[38 coupe]

Asking what oil to run is a dangerous thing on an internet forum. You will get lots of opinions. You will also be warned about zinc. Please be aware that zinc (ZDDP) was added to oil in the late 50s, well after our engines were built and run with no problems. Zinc is needed for higher rpm overhead valve pushrod engines with lots more valve spring pressure than we run. You don't need to worry about zinc in your 1952 Ford engine.

I use 15W40 diesel oil and find I have better hot idle oil pressure. Your situation may vary.
Also, if you have a flathead V8 with an oil filter, does it have the proper restrictor fitting at the oil filter inlet?

[19Fordy]

I live in FL and use Castrol 20W-50 in my 1953 Ford v-8 engine.

[petehoovie]

Originally Posted by jplutz

Greetings & Salutations,
I just got this beauty back on the road after rebuilding 95% of the brake system. When I changed the oil & filter, I put in 10w30 cuz that's what I had. At idle, cold, the pressure is great, as per photo. And driving around the neighborhood it still stays good. But..The other day in 90deg heat I took her out on the local highway for a 2 mile round trip drive, and by the time I was returning home the pressure was in the pits, unless I reved the engine and raced down the road.
I realize that I screwed up with the oil. What weight should be used? I have a gallon jug of 5w40. Is that ok, or is the 5 side too lite? Is there a brand that is best? BTW, the engine did not overheat, the temp was steady.
Thanking you in advance, I remain
Yours Truly, JP Lutz
ps. I have dog dish on one side & baby moons on the other, and I paid thru the nose for the patina.. ha, ha!!

[Jumbogem29]

I run the 15-40 diesel oil as well i live in the south i use Delo

[Bill OH]

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I use 5 W 20 Mobil 1 in a 221 with 10K miles since rebuild. Oil pressure 35lbs on road.

[glennpm]

15W-40 Shell Rotella T4 Diesel Oil, not synthetic.

[KiWinUS]

Do a search on here. The information will blow your phone up. This question gets asked every week.

[HDowse]

Lots of opinions and suggestions but you won’t go wrong either with 15-40 Rotella or any brand 20-50. Chalk up your 10-30 experience as a quick oil change to clean out the engine. Good luck and have fun with your car.

[alanwoodieman]

I will add my two cents worth--20w50 in any brand available, also I usually put in some lucas oil extender about 1/2 quart for already run in engines and older engines--have fun with the car and do not worry about the patina it is great!!

[Ken/Alabama]

Originally Posted by KiWinUS

Do a search on here. The information will blow your phone up. This question gets asked every week.

Exactly!!

[JayChicago]

I’ve heard it said you are OK as long as you have some pressure. Your engine doesn’t need a lot of oil pressure, just enough pressure to get oil distributed everywhere.

[Flathead Fever]

I use the 15W40 "Diesel Oil" in the flatheads. The reason for the diesel oil is it still has anti wear additives which protect flat tappet cams and lifters which your flathead has. I was a mechanic for the phone company for 30-years. We were only allowed to stock one type of oil in the fleet so the 15W40 diesel oil was chosen. The trucks would fall apart before the engines ever wore out.

[GB SISSON]

Another 15-40 dino diesel guy year round up here in the NW corner.

[aussie merc]

well the never ending story look at your average summer and winter temps this will set your xw/y range you may even have to have a summer and a winter oil i found that some of the repair manuals from the late seventies early eighties had a chart showing oil types for temperature range I'm in Sydney Australia so about the same latitude as Longbeach and i run a 20w/50 and oil pressure seems stable

[cas3]

15 40 diesel of the cheapest available. Fleet farm brand, 2 gallon jug 4 years ago...16 bucks. 2 years ago 22 bucks. today, 32 bucks. who you vote for matters.

[Jack E/NJ]

I vote for 0w-20 Walmart SuperTech brand.

[jplutz]

Thank You all for your responses. It looks like I will have to chalk it up to giving the engine an internal cleaning as HDowse says. From all the responses, it seems that 15W40 is the favorite for maintaining good pressure. So I have some shopping to do.
38 Coupe, I'm attaching pics of my oil filter fittings. I don't know how to tell if I have the proper set-up. I bought it this way: it may be rebuilt, the block and timing cover are a limy green, the passenger head is painted red over blue or primer, the intake and water pumps are orange, the driver side head is red over green. The pass head has screw- tag over the Logo marked N 691, or G91, and has a 3 stamped at the bottom, the driver side only has a 5 stamped below the Logo. The intake is marked 8BA 8RT 8520 behind the carb.
I personally have no way of telling if these are original or replaced. From prior inquiries on the Barn, I know the carb is from a 55/56 Y block, with the choke mechanism removed. The timing is spot-on with the Loadamatic. I changed the plugs, cap and rotor. It starts on the first rotation, every time, with an Optima RedTop and tends to run rich, typical of Flatties. Also, it has a 6v alternator.
So I'll attach some photos an maybe 38, you can tell if I have the correct oil fitting.
Also, thanks alanwoodieman for the compliment; it took a lot of elbow grease!! Ha, ha. It must be from the sea shore area?!
Yours Truly, JP Lutz

[petehoovie]

Originally Posted by jplutz

Thank You all for your responses. It looks like I will have to chalk it up to giving the engine an internal cleaning as HDowse says. From all the responses, it seems that 15W40 is the favorite for maintaining good pressure. So I have some shopping to do.
38 Coupe, I'm attaching pics of my oil filter fittings. I don't know how to tell if I have the proper set-up. I bought it this way: it may be rebuilt, the block and timing cover are a limy green, the passenger head is painted red over blue or primer, the intake and water pumps are orange, the driver side head is red over green. The pass head has screw- tag over the Logo marked N 691, or G91, and has a 3 stamped at the bottom, the driver side only has a 5 stamped below the Logo. The intake is marked 8BA 8RT 8520 behind the carb.
I personally have no way of telling if these are original or replaced. From prior inquiries on the Barn, I know the carb is from a 55/56 Y block, with the choke mechanism removed. The timing is spot-on with the Loadamatic. I changed the plugs, cap and rotor. It starts on the first rotation, every time, with an Optima RedTop and tends to run rich, typical of Flatties. Also, it has a 6v alternator.
So I'll attach some photos an maybe 38, you can tell if I have the correct oil fitting.
Also, thanks alanwoodieman for the compliment; it took a lot of elbow grease!! Ha, ha. It must be from the sea shore area?!
Yours Truly, JP Lutz

[ct1932ford]

Valvoline VR-1 Racing oil 20/50