1956 312 best Oil type

[Ward 57]

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?

My shop which specializes in classic Mustangs recommends Castrol GTX High Milage 10-40. It has plenty of ZDDP and is more brown in color VS. others that are amber. I have a quart of 20-50 to top off when needed. ( darn rear crank seal ) .

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[willcarterdc]

For my most recent oil change on my ‘57 (which was also my first oil change since owning it), I went with Rotella based on the many recommendations here and elsewhere along with a quart of Marvel Mystery Oil. When I change the oil again this fall, though, I’m going to try this “classic motor oil” from the Marvel Mystery folks:

MARVEL® CLASSIC MOTOR OIL 32OZ

Marvel Classic Motor Oil is proprietarily designed for classic cars. Classic car engines face a different set of challenges than today’s new car engines. Today’s reformulated new car engine oils don’t have all the anti-wear additives that classic car engines were designed to have, which can lead...

marvelmysteryoil.com

 

[zeroroadkill]

To each his own, but I use Valvoline VR1 racing oil 20W-50 (summer) (stock engine) VR1 has zinc added. Or you can use any other ? Dino oil with a zinc additive. I’ve never used synthetic for fear of new oil leaks and I don’t drive >2000 miles a year between oil changes. No need to spend the $$$ for synthetic if you change your oil once a year IMHO.

Good article

The Effects of Zinc Oil Additives on Older Engines | Rislone

Almost everyone who’s into cars has an older vehicle that they love. Whether it’s the feeling that they get behind the wheel or the way the car looks parked in their driveway, they pour their time and effort into maintaining the car and keeping it looking like it’s just been driven off of the...

rislone.com

 

[55birdman]

Remember that this engine has flat tappets and not roller tappets as do most modern engines. This is the primary reason for the use of zinc additives or oils that contain higher levels of zinc which will reduce the sliding friction.

 

[Ward 57]

To each his own, but I use Valvoline VR1 racing oil 20W-50 (summer) (stock engine) VR1 has zinc added. Or you can use any other ? Dino oil with a zinc additive. I’ve never used synthetic for fear of new oil leaks and I don’t drive >2000 miles a year between oil changes. No need to spend the $$$ for synthetic if you change your oil once a year IMHO.

I agree with you. A new engine, sure go synthetic, but you don't want to upset any chemistry in your oil. I remember in the 70's there was a big argument about Pennsylvania oil and other origins and you couldn't mix the two. Probably mostly just marketing to preserve market share, but it stuck.

 

[jsonny]

“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.

Seems we all go through the question of the type of oil. I selected Valvoline VR-1 Racing Oil because of its high Zink compound, which is important, and it was easier to obtain. There are other brands available, just insure that it has Zink due to our upper engine components.

 

[Nico57]

good grief..I just read the comments..I need a moment.: Rotella is for diesel..can it be used, yes but it is formulated for diesel and other engine oils are formulated for gasoline engines. The engines are flat tappet cams..at the time made zddp was in engine oil to minimize wear in metal to metal contact where there was pressure. (cams) Most oil now does not have it..not needed for the cams and metal of today, and interferes with a catalytic conv. Does your 55-56-57 have a cat converter? NO..does it have a flat tappet cam YES. Use any major brand engine oil that has 1000 to 1200 ppm (some are 1400 which is ok but not ideal). of zddp. Do not try to mix zddp in oils that do not have it, unless you know how to get 1000 to 1200ppm. There are plenty of oils already in the range and identified as such. An oil that is a racing oil in NOT appropriate: it is meant to be changed every race, it is meant for wide open throttle, it is meant not to foam, it has far less if any detergent and anit sludge, and anti acid as it is to be dumped after the race. Mobil 1 15-50 has the appropriate zccp (other Mobil 1 viscosities do not), Castrol Classic is 1400ppm--OK, Joe Gibbs and others do as well. Viscosity you select does not matter much, but these engiines run hot so a higher viscosity is a good idea. Multi grade is fine. Just don't use modern 5W 20 and similar for new cars--which has low if any zddp anyway. I suggest the Mobil 1 15-50..it takes care of all. But the standard 10-30, or 20-40,etc are ok as long as zddp 1000 to 1200 (1400 tops) ppm. The 1400 and some higher are meant for muscle cars and racing with much higher valve spring pressures running at sustained high rpm. OK tho.
I won't even start with discussing "additives" to improve what the major oil company engineers "forgot " to formulate. Admitting some additives do temporarily help with existing problems (blow by, leaky seals) ..but a sound engine won't need em. Research the web realizing that a lot is "my uncle had a cousin whose friend had a tractor and he said he used.......and it was perfect for 700,000 miles. etc."
Nick