What is the recommended engine oil for the 455 Rocket engine?

 

10w-30 and 10w-40 is what the factory recommended depending on the average outside air temp.

 

How many miles on it? Fresh rebuild? If fresh what was the bearing clearences set to and what type of oil pump? What climate do you drive it in? Whats your current idle and at speed oil pressure?
Generally 10W30 is good all the way up to 20W50. Thinner is better in colder weather. Opposite for Dessert weather. You'll get plenty of opinions here. Its a personal choice. So that's why I provided a range. Use a high quality oil made for flat tappet cams...if thats what your running. Several vendors cater to this crowd. You need high ZDDP content with flat tappet cams.
I use 15W40 Rotella "T"or Shaeffers 15W40. I also run with a can of Prolong.

 

Truth. ^^^


I'd venture to say that zinc content is even more important than specific weight. Specialty suppliers like Edelbrock make high ZDDP formulae intended for use in old cars but they're pricey. Lucas also makes a high-Zinc variant which I've been using in my 400G for awhile with no problems.


As to weight, you'll likely be fine with 10W-30 or 10W-40 under most conditions.

 

I've used Rotella T 15W40 for 25 years in my 400.

Engine has never been apart...

 

I run Joe Gibbs Racing 20w 50 in my 68 400. I live in the desert and this works good for me a bit spendy but very good product

 

How often should I change my oil? Do I go by miles or time? I barely drive it (1,200 in 10 months - temp in my garage ranges from 50F - 85F).

 

I'd change it once or twice a year then.

 

I do mine every fall before I put it away for the winter.

I just read that back and it sounds funny. I meant the car.