"Most companies put the shelf life at about a year and advise you not to use it beyond that." I guess I must be King Cheapskate because for many years I have been using almost exclusively, Flea market, swap meet and garage sale oil that is probably up to twenty years old, in both the old cars and modern family fleet. No problems yet. It's no surprise that the oil companies will advise throwing away the old oil after a year and buying more. Remember the (was it Pennzoil?) ads where people would write in with questions like "should I change the oil in may garage kept unused car twice a year?" Well, yes, of course.
I've met and spoken with some who change their oil before they store the car, then change it again when they take it out for the season. "Why would you do that?" I ask. "It settles and all the good stuff is on the bottom." "uh, ok..." I should ask them for their drained "storage oil", huh? And no, they don't start the car at all. I think the car, under a cover, battery tender hooked up and left alone is a greater danger than "settling oil", no? The black magic of oil is viewed religiously by some, they DON'T want to know anything new or updated, likely won't believe you either. I knew another guy who put 7 qts of fresh Mobil 1 in the race car every weekend, but at least he used the drain oil in his daily drivers. I suggested he could use something much easier on his wallet, and maybe see a performance gain as well. Nope. Not having any of it. So I offered him a copy of Super Stock where they dyno tested 5 oils. 4 synthetics and one mineral. Of the 4 synths, Redline, Torco and Amsoil all made add'l HP over the mineral. Mobil 1 took away 11 HP! Torco made the most, almost 20 add'l HP. This was a 1200 +- HP 500 CID race engine, similar to a Top Sportsman car of the day. Once back to mineral oil (Valvoline I think) the engine still maintained a slight performance edge having had synthetic in it for all the testing, but there was no follow up on how long that lasted. the Mobil 1 thing caught me by surprise. Anyone remember that article? it was titled "Snake Oil or..." I bet I have it somewhere, but where?
If any of the "good stuff" settles out after a few months (or years), I bet it mixes up pretty quick when the oil starts to circulate when the engine starts, and then warms up.
So I’ve been using CJ-4 for the last few oil changes (SBC with Crane Fireball II cam). CJ-4 is gone now, CK-4 is the new replacement. Sounds like CK-4 should be ok. But I have about a half jug of CJ-4 left, probably 3 to 4 qts. Is it ok to mix CJ-4 with CK-4? Sent from my iPad using H.A.M.B.
My understanding is that the 800 ppm limit is really only applicable for dual-rated (CK-4/SN) 30-grade HDEOs. If a 40-grade HDEO has an additive package that meets the performance requirements of CK-4, can this same additive package also meet the performance requirements of CK--4/SN or would it need a different formulation to get the dual rating? I've been using Petro Canada Duron SHP 10W-30 which has both API CK-4 & Ford WSS‐M2C171‐F1 but has the same additive package for Duron SHP 15W-40 (API CK-4/SN & Ford WSS‐M2C171‐F1). Shell Rotella T4 now only has diesel ratings (no Ford WSS‐M2C171‐F1 either) and no longer has any S-ratings. Rotella T4's lack of SN for 15W-40 suggests to me that they would have different formulations.
I don't believe the requirements are limited to 30 grade oils. So if the oil is dual licensed, for both CK-4 & SN, then if must meet the more stringent Zinc & Phosphorus restrictions, regardless of viscosity grade. That is why dual licensed products, like Delo 400, now have reduced levels of Zinc. I just downloaded and reviewed almost 250 oil samples of Rotella T 15W40, since July 1 of this year to current, and the level of zinc remains well above 1000 ppm. Note, Ford lists Rotella T3 & T4 & T5 as meeting the WSS-M2C171-F1 spec. It does not list Delo 400.
Jims oil tests from back on the first page and his statements show his reasons for not adding ZDDP. Even tho I added it when changing oil in the past I didn't do it the last time. I checked my valve spring pressure and deemed unnecessary. 55-65 psi is just not enough to worry about it. On our race engine using a flat tappet cam we only use it for breakin. We use only Delo 400 and the cam and lifters show no wear with spring pressure of 135. Jims choice of oil shows how good it is after 2500 miles of use.
This is my understanding based on discussions with Petro Canada's tech department. If you look at the Infineum API performance criteria, you will see the following: The first item in the SN specifications is Viscosity Grades: All those that apply, typically SAE 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30. [These are the viscosity grades that can potentially meet ILSAC specs for passenger car motor oils formulated with fuel economy in mind (API calls it Resource Conserving, API SN-RC).] API SN specifies that there is 0.08% maximum for phosphorus. However, there are 3 footnotes: (4) No maximum for SN Non-ILSAC GF-5 viscosity grades. [These are the XXW-40 grades.] (9) For all viscosity grades: If API CH-4, CI-4 and/or CJ-4 categories precede the “S” category and there is no API Certification Mark, the “S” category limits for phosphorus, sulfur, and the EOST MHT do not apply. However, the CJ-4 limits for phosphorus and sulfur do apply for CJ-4 oils. (10) This is a non-critical specification as described in ASTM D3244. Therefore, because 5W-30 and 10W-30 are ILSAC GF-5 grades, API SN requires a maximum phosphorus content of 0.08% for these grades, which is not critical. Footnote 4 removes the 800 ppm maximum for 40-grade oils. Footnote 9 allows CJ-4/SN oils to have up to 0.12% of P but leaves out mention of CK-4. Footnote 10 allows oil manufacturers to have phosphorus levels up to 0.12% to meet API CK-4, regardless of grade. Presumably, the Ford WSS-M2C171-F1 specification came about because some oil manufacturers had phosphorus levels closer to 0.08% rather than 0.12%.
As an aside, what is done differently with oils advertised as being for "high mileage" cars? Is there some property that actually is better for a semi-tired engine or are we, yet again, being taken for a ride?
In general, yes it should be OK, in that there should not be any kind of negative reaction that would result in harmful byproducts. The CJ-4 product will dilute the advantages of the CK-4 product. Best practice is to stick to 1 product and not mix them, but in real world situations that is not always practical.
Blues4U, have you read this blog? I found it on the p-15d-24 site. It seems to place more importance on psi values than zinc for longevity. https://540ratblog.wordpress.com
The Jalopy Journal
