And here’s info that’s been touched on in the recent past. Any new oil with an API classification of SM and with 40W or more in its viscosity rating will have the necessary amount of zinc/phosphorus content to work with the flat tappet camshafts in the older engines including the Y’s. It’s only the SL or SM oils with 30W or less on their labels that have the reduced amounts of ZDDP. So stick with your favorite brand and just pay attention to the viscosity rating. I’ll add (and this is just my opinion) that additives and special oils are over-rated for the majority of street driven vehicles if the correct oil for the application is selected to begin with. Here is a past thread on the subject. Performing a search on this site using zinc or zddp will also bring up several more.

http://forums.y-blocksforever.com/Topic9285-3-1.aspx

Lorena, Texas (South of Waco)

Again, the apparent problem with long term exclusive use of diesel oil is: the aggressive detergent action strips away the built-up layer of protective zinc. I would think that using it (especially the older, higher zinc Rotella formula) in a very dirty engine would be a good thing, if the sludge is kept in suspension? Alternating with a high-zinc gasoline racing oil should renew the protective layer?

6 VOLTS/POS. GRD. NW INDIANA

Where does the 1400 come from? Back in the 50 and 60's most oils had less than 1000

54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

A few weeks ago I ran a 390 FE on the dyno and did the break-in with Castrol GTX 5W30 and 1 bottle of Comp Cams Break-In Lube.  It's running a fairly aggressive flat tappet cam with 427 low riser valve springs.  No problems with the brake in and once I get the engine in the car it'll get Castrol GTX 20W50 and another bottle of the Comp Cams Break-In Lube. Then just 20X50 Castrol GTX.  It's really the break-in where you need the added zinc.

Leave the Diesel oil to the truckers, it has too much of a detergent package for a gasoline engine..  If you don't like Castrol oil Mobil 1 High-Mileage 10W40 has 1000 ppm of ZDDP in it.  For that matter anything with a High-Mileage label is made for older engines and will have enough of the anti-scuff ingredients in it to to keep a flat-tappet engine alive on the street.  For racing, use an oil formulated for racing, but don't use racing oil for the street.

As Ted and others have said, anything with a rating above 40 is OK, just avoid oils that have a label stating greater fuel economy and less friction, they're for the newer roller-cam engines.

Larry D

Winnipeg, MB Canada Eh!


'57 Fairlane 500 Club Victoria

'58 Custom 300 Tudor

'56 Crown Victoria

'61 Starliner Z Code

'51 Ford Victoria

Me too. The Valvoline guy told me it was fine. It says right on the bottle it is for flat tappet motors.



All of this talk about break in oils etc, back in the day I rebuilt a lot of motors and I never used any special anything, there was no special break in stuff. I put the motor together with STP drippin' off of everything and started the engine with non-detergent oil. The first oil change I changed to detergent oil. I never had a problem then and wouldn't expect to have one now.

Doing Fords for 45 years. '56 Customline Victoria

E.J. in Havana FL

Ford engine plants don't use "break-in" oil, either.  It's regular multi-viscosity oil with a dye that shows up under black light (for oil leak detection).  The difference is, production engines are run soon after they are assembled (cold test, then hot test).

Ours engines are rarely run until they are in the car.

For "break-in" oil, I mix red STP with a little 10W-30.  It hangs on and has no problem mixing with the real oil as it washes away under normal running.

Royal Oak, Michigan (Four miles north of Detroit, and 12 miles NORTH of Windsor, Canada).  That's right, we're north of Canada.

Ford 292 Y-Block major overhaul by simplyconnected