1956 312 best Oil type

I myself just add a bottle of Marvel Mystery oil with each oil change. Along with Lucas hot rod oil. Which contains a lot of zinc.
I've heard many testimonials about marvel mystery oil. Don't know what it's made of But spraying it into the spark plug holes of engines that haven't run in years and letting it soak in and free up the rings are not disputed.
 
Back in the early 1990’s we used 60 and 70wt oil in some of those old old Harleys thinking that the air cooled engine along with higher viscosity would coat the machinery inside like that old LUCAS oil additive display crank in the auto stores. After really reading the 540RAT blog, I’m 90% sure that was a mistake.

While not a widespread practice at the time, My 2001 F-150 used synthetic since day 1 and I traded it 16 years later with 297,000 miles and not one problem ever. A navy helicopter pilot friend used synthetic in his 1988 Harley for 160,000 miles. and utilized the “military” machine shop in measuring his wear components and had zero wear… an eye opening measurement. Clearly MUCH more to oils that I believe we know about. 540RAT says do not add anything to your oils. I bought 6 bottles of ZDDP Plus but I’m not going to use them based on the test results in the 540blog paper. At work, 70% of the fleet are diesel trucks and I brought this to the attention of our head mechanic. I’m waiting to get that opinion. I’m afraid it will come out as….I’m not changing anything..something screws up and it’s my job that goes away
 
I use Valvoline VR1 10w 30. I use this oil because of the high Zinc levels for the solid cam and lifters. Back when these cars were built, the oil available had lots of zinc (a wear agent) today's oil has very minimal zinc if any. Anytime you run a solid lifter / cam set up, you should run an oil with zinc.
 
Why not look at Valvoline VR1. It states on the jug that it has high zinc/phosphorous, designed for push-rod engines & flat tappet cams.
I would not use diesel oil in a gasoline engine, but to each his own. Everone has their own opinion.
 
I use Valvoline VR1 10w 30. I use this oil because of the high Zinc levels for the solid cam and lifters. Back when these cars were built, the oil available had lots of zinc (a wear agent) today's oil has very minimal zinc if any. Anytime you run a solid lifter / cam set up, you should run an oil with zinc.
I think there is a lot of misinformation about the amount of ZDDP (Zinc dialkyldithiophosphates) and the amount needed for the early Birds. On a analysis commissioned by a leading Tbird restorer he found that a oil produced in the early 80's (Pennzoil 10-40) had only 716 PPM of Zinc. Compare this to a current oil (Valvoline conventional) 10-40 which has a little over 800 ppm of zinc. A noted YBlock engine builder uses Valvoline conventional 10-30 or 10-40 in his engine builds.
 
I would never dispute someone else's work or experiences, but take a few minutes and read the PI on the Valvoline VR1 Racing Oils..Valvoline VR1 Racing Oils
I read it and I like it. I also read the 540RAT blog and the logic in both makes sense. I like the part in the 540blog that describes why additives over and above the manufacturers formulations are ill-advised. That makes a lot of sense to me as well, so if it’s in there to start with, I’m happy.

I believe we are so conditioned to ignore some of the chemistry behind it and look at the ad slogans that when I could pour in a bottle of “stuff’, it makes me think I’ve improved things. The reality is, I have not got a clue. I’ll try that VR 1. I would change the oil in my bikes routinely even though the mileage was low… crazy human habits don’t go away easily.
 
I use Valvoline VR1 10w 30. I use this oil because of the high Zinc levels for the solid cam and lifters. Back when these cars were built, the oil available had lots of zinc (a wear agent) today's oil has very minimal zinc if any. Anytime you run a solid lifter / cam set up, you should run an oil with zinc.
That is a good oil for old flat tappet classics with original drivetrain, as is Mobil 1 15W-50W (formulated for older cars with original engines).

I've used both (switching from Mobil 1 to the VR1) for decades in my 61 solid lifter Corvette and my 63 Corvette split window (a $150,000 car) with no issues... Use either one and you won't have to agonize over this anymore. NAPA used to carry them both, maybe they still do.

Attached are the ZDDP specs for the Mobil 1 15w-502
Mob1.JPG
 
That is a good oil for old flat tappet classics with original drivetrain, as is Mobil 1 15W-50W (formulated for older cars with original engines).

I've used both (switching from Mobil 1 to the VR1) for decades in my 61 solid lifter Corvette and my 63 Corvette split window (a $150,000 car) with no issues... Use either one and you won't have to agonize over this anymore. NAPA used to carry them both, maybe they still do.

Attached are the ZDDP specs for the Mobil 1 15w-502
View attachment 20231
I was ordering the Valvoline VR1 Racing via Amazon because of the price. Napa has it in stock, but its twice the money...
 
56 thunderbird 312.
Who has the most experience here and which oil and or additive should I use? I live in NY and would love the best information from an expert. Any experts/oldschool guys here? No weekend warriors need respond. Lol!
Thanks,
Bill A
 
Engine oil has always been an interesting topic as well as constantly changing to accommodate modern engine technology.

Hot Rod Magazine covered the subject very well in an article published June 2006 titled “When Good Cams Go Bad”. Comp Cams also has an excellent Tech Bulletin titled Flat Tappet cam shafts.

rotella-t.jpg
aspi.jpg
15w-40.jpg

All modern high tech engines with push rods use roller tappets and overhead-cam engines use either roller or sliding tappets.

“In an ongoing attempt to keep emissions as low as possible, manufactures have been putting tighter and tighter limits on how much phosphorous and zinc can be in the motor oil” Mark Ferner, Quaker State.

Older engines including all early Thunderbirds have flat tappets. “Engines with flat-tappet cams have extremely high pressure loading at the contact point between the lifter crown and cam lobe” (Hot Rod Magazine). In the past conventional motor oil included a generous supply of anti-wear additives, a combination of zinc and phosphorous (ZDDP). Ferner adds, “The zinc reacts with the cam lobe’s iron surface and creates a sacrificial coating strong enough to keep parts separated to reduce the wear.” ZDDP is not required in modern engines and has been reduced in most modern oils because as it flows through the exhaust system on worn engines it has been blamed on degrading oxygen sensors and catalytic converters. “It will only get worst because projected future oil spec revisions will likely reduce ZDDP content even more” Hot Rod Magazine.

OK, What can we do? It is not all gloom and doom for our Thunderbirds. The Hot Rod Magazine article as well as the COMP CAMS Tech Bulletin emphasizes the importance of oil with ZDDP during the camshaft break-in period. Most engine shops can provide the proper oil for camshaft break-in and NAPA and other stores also have camshaft break-in oil.

All engine oil containers have API Service ratings on the exterior of the container. Modern heavy-duty diesel engine oils have lots of ZDDP additives and will be marked “CI-4 or CI-4 Plus” Diesel oils also have additives that pass all gasoline engine performance tests. Some racing oils also have adequate amount of ZDDP. Check the API ratings on the container.

Hot Rod Magazine list the following API designations or brands as having ZDDP content: SM, SJ, SL, SM, Cosworth Racing, Shell Rotella T, Pennzoil 20W-50W Racing and Quaker State Q Racing.

I recommend reviewing (Google) the comments made on line regarding engine oil, the Hot Rod Magazine article and the COMP CAM Service Bulletin.
 
Shell Rotella T4 15W-40 only.

Yes, while referred to as 'diesel oil', based on lab analysis, it has more ZDDP in it than was the original oil recommended for use in 1956 ... so, no additional ZDDP additive is necessary.

I change my oil and filter once per year before storage. My mileage each year varies, but it is generally limited to less than 1500 miles. The used oil comes out very dark, so I assume the 'diesel' additive package is doing something good for my engine.
 
I'm also an MMO fan of many years.
Any CJ-4 rated oil will work in these engines and no additives required for the proper ZDDP leverls.
If you want to use synthetic then Mobil 1 15W-50W works perfectly..... Many NAPAs have it on the shelf or
can get it the next day.

.I've used it for years in original solid lifter engines revved to 6,800 RPM; you can read the levels of ZDDP in the attachment for that viscosity.
There is no reason to make things complicated with ZDDP separately added or other snake oil.
Neither Seafoam or MMO or Techron add ZDDP BTW..Mob1.JPG
 
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My dad just got a 56 with a 312 and a automatic transmission. What type of oil is recommended? Any help is appreciated. I read he should use rottela t 15-40 becaue it has zinc . Not sure if that is what we need?
Best oil to use for these engines should have a high zinc content
 
I recently purchased a 1955. Want to oil change it however I keep finding conflicts as to which weight of oil is best for it as well as synthetic versus conventional or a blend. Some say Rotella 15-40 which is basically for diesel engines. Some say use 10-40. I found Quaker State 10-40 all miles? Just want to be sure I use the best one for my car. Thoughts?
 
Probably most people would agree with 10-40. I use 15-40 because of the additives in the oil. It also depends on the condition of the engine. Was it just rebuilt? Is it high mileage? My engine was just rebuilt I will use 15-40 because of the high Zinc content in the oil. I'll run it 1000 miles then change to a good 10-40.
 
The shop manual says straight 20 or 20w I put 5w 20 in mine not too long ago 6 quarts and a NAPA filter #1004 (fuel filter) NAPA # 3034 or car quest # 86034 get a couple in case you need to change it have one on hand in the glove box.
 
“Lucas Oil” makes a hot rod oil
Specifically formulated with high zinc content for older solid lifter flat tappet engines. NAPA can order it for you if they don’t stock it.
I’ve also used the rotella 15-40 with an additional zinc addative.
 
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