Oil question for Duke

[Scott Landis]

Duke,
I just purchased some Valvoline 15W-40 HD diesel oil for my 67 327/350 and noticed ratings of CH-4 and CG-4. Is my supplier selling old stock, and if so, is it any good? What is the difference with these ratings and CI-4, and what brands are rated at CI-4?
Scott

[Duke W.]

Re: Oil question for Duke

Yes, it sounds like old stock. CI-4 replaced CH-4 two years ago and CH-4 replaced CG-4 prior to that, however, no real harm will be done if you use it. I can't state the detailed differences between the test specs, but generally the requirements are upgraded with each new specification release.

If you can't return what you bought, go a ahead and use it. I use Chevron Delo 15W-40, and I can buy it at Costco or most of the chain auto parts stores in gallon jugs for about six bucks.

The other major national brands of CI-4 oil are Shell Rotella and Mobil Delvac, but buying the proper API spec oil is more important than brand name.

The American Petroleum Institue web site has a discussion of the API certification standards for both motor oils and gear oils. I suggest than everyone visit the following web page and view/download the information on motor and gear oils. You'll be much more knowledgeable the next time you need to purchase any kind of oil.

http://api-ec.api.org/about/index.cfm?bitmask=001002003002000000

Duke