Slick 60's

Recomended oil for the 352 ?

10W30 or 10W40 Motorcraft Syn Blend. 30 winter, 40 summer.

I've always run 10w-40 in the cold weather and 20w-50 in hot weather, on engines with a few miles on them....

I use 20-50. Old engines will use oil; the thicker oil tends to stem the tide of the burning/leaking even in ones in good order.
Also, as hot as these big lumps of cast iron tend to run, I think the thicker oil is better and won't thin out too much.

NJ2000R wrote:I've always run 10w-40 in the cold weather and 20w-50 in hot weather, on engines with a few miles on them....

Same here.
10-40 turns to water in the hottest part of summer, 20-50 seems better. However, 20-50 turns to molasses in extreme cold & makes it hard to start in the mornings because the oil pump is having a hard time pumping molasses.

Guys.
I respectfully disagree on the multi-grade oils on old motors like outs except in cold climates like where Iceman lives.
I would suggest the best grade of single weight HD-30 for summer driving for you yankees or HD-40 if you live where the temperature goes above 90 on a daily basis like we do in the sunny south (I use the 30wt for all year driving but only because Nadine has a new motor).
Change the oil and filter on a regular basis and its all good.
Just my dos peso's worth.
Tio Skip

the 30w in my air cleaner is so thick when its real cold that the truck runs rich.i have been thinking of using atf in the oil bath cleaner.
10w30 is ok here in my engine when its cold but still thins out too much when the engine warms up.

30 W HD

Modern lubricants and additives are so much better today than 40 years ago that I have no worries about multigrade oils. With all due respect to our Texas colleagues, I think the only place that heavy straight weight oils are useful is in industrial applications and racing, where frequent and/or cold starts are rare.

I would assert that if you are starting an engine in cold weather, you want as low a winter rating possible. There are some very good 10w40 and even 5w40 oils these days that are stable for thousands of miles.

Perhaps more importantly though, is that modern GAS oils may be losing some of their qualities in terms of additives. Mainly the ZDDP which is zinc is now being reduced to make the catalytics last longer.

I am convinced that the best oil these days for an old flat tappet gas enigne that has no pollution controls is a multi visc, synthetic or semi-synthetic HDEO for diesel. There are several makes of 5w40 out there are are great oils, in terms of their additive packages and viscocity ranges. Mobil Delvac 1 or Cenex Maxtron Deo are a couple of examples.

bobistheoilguy.com is a great place to read about it, if you want more.....

I run Havoline 10w30 in the winter and 10w-40 in the summer.

I run 5w40 Rotella T Synthetic Diesel oil all year around in my 292.