Zinc in Rotella T

[Duke W.]

Re: Zinc in Rotella T

Is there any reason not to use a CJ-4 oil in a newer (2005) engine with high mileage?
Steve

It depends on the internal design details of the engine. If there are no sliding surfaces in the valve train, then the additional ZDDP in CJ-4 is of no benefit since its primary purpose is to protect sliding surface valve train components.

The reason why ZDDP is reduced in current S-category oils is that phosphorous is thought to be a factor in catalyst aging, and manufacturers have been required by the EPA to increase emission system warranties, so the industry via the API decided to reduce ZDDP to 1950s levels in S-category oils. The compensating factor is the elimination of sliding surfaces in modern engine valve trains.

Most modern engines going back at least ten years including OHC and DOHC designs use full roller rocker arms - a roller trunnion with a roller in contact with the camshaft. The GM Ecotec and LS-X engines are good examples. There are no valve train sliding surfaces in these designs.

As a general rule - unless there are overriding considerations due to design details - I recommend using the OEM recommended oil service category and viscosity in modern engines.

My catalyst equipped engines - including a 1988 and 1991 model - have sliding surfaces in the valvetrain, so I use CJ-4 in them. They have low mileage with low rates of mileage accumulation and good emission test performance, so I am not concerned about ever having to replace the catalysts.

Duke

[Harry L.]

Re: Zinc in Rotella T

I have a 66 big block with factory air. When I need an oil change, I go to Walmart, pick up the house brand 15/40 C-J-4, and that is all my car needs to keep running strong. Of course we need an oil filter. DUTCH

[Duke W.]

Re: Zinc in Rotella T

I use Walmat's "SuperTech" 15W-40 CJ-4 myself. It's less expensive than the national brands, but often not in stock at my closest Walmart in Torrance CA.

Get some Baldwin filters and you've got the best for the least.

Duke

[Wayne L.]

Re: Zinc in Rotella T

The last time I looked at oil, Rotella T4 was rated CJ-4, but Rotella T5 was rated CJ-4.

[Ted K.]

Re: Zinc in Rotella T

Rotella T3 is gas, Rotella T4 is diesel, what is Rotella T5 recommended for?

[Wayne L.]

Re: Zinc in Rotella T

Ted-
My post should have said Rotella T5 was not rated CJ-4. I will need to go back to Walmart and/or Fred Meyer to find T5 again. Will let you know what I find.
Wayne

[Duke W.]

Re: Zinc in Rotella T

Rotella T3 is gas, Rotella T4 is diesel, what is Rotella T5 recommended for?

ALL "Rotella" branded oils are primary C-category. I think all the T-nonsense has to do with whether it's 5W-40 or 15W-40. I'm not sure. It's confusing and probably the reason I have NEVER bought Rotella. Leave it up to a bunch of marketing morons to screw up your product identity.

When I go to Walmart to buy C-category oil I usually buy their SuperTech house brand because it usually less expensive than any of the national brands, but occasionally Delo or Delvac is on sale and less expensive than SuperTech, so that's what I buy.

That's why I admonish all to ignore all the marketing BS. Just look for a primary C-category in the proper viscosity range for your lowest consistent cold start temperature, and buy on price. It's a generic product.

Duke

[Dick W.]

Re: Zinc in Rotella T

Ted-
My post should have said Rotella T5 was not rated CJ-4. I will need to go back to Walmart and/or Fred Meyer to find T5 again. Will let you know what I find.
Wayne

It is a synthetic blend. It carries the CK 4 designation which is backwards compatible with CJ 4

[Joe L.]

Re: Zinc in Rotella T

Is there any reason not to use a CJ-4 oil in a newer (2005) engine with high mileage?
Steve

Steve------


I would not use any C-rated oil in a 2005 vehicle unless the oil was specifically dual-rated for S service. Even then, I'd probably not use it.

I would recommend using S-rated oils specified as "high mileage" (usually stated as 75,000+ miles). I've used these in some of my higher mileage cars and found that they significantly reduce oil consumption. They do cost a bit more but I would not think enough to discourage anyone from using them.

As far as viscosity goes, in a modern car I would use nothing but the viscosity recommended by the auto manufacturer and described in the owner's manual.

[Duke W.]

Re: Zinc in Rotella T

Steve------


I would not use any C-rated oil in a 2005 vehicle unless the oil was specifically dual-rated for S service. Even then, I'd probably not use it.

.

It's really about the valve gear. If it has sliding surfaces and not "roller everything" then C-category may be an advantage, but the higher P concentration could possibly degrade the catalyst(s) faster, especially if oil consumption is relatively high.

Duke

[William F.]

Re: Zinc in Rotella T

Duke,
Hate to bring this Rotella T thing back up but I just noticed some differences on label of T4 and the other jug labeled jus "Rotella T." Both jugs are 10W30. T4 jug says "heavy duty diesel oil" and has only C ratings no mention of an S rating. The jug labeled just Rotella T has multiple C ratings plus CF/SN.
1.Does this mean the T4 has more ZDDP since it's just rated for diesels only and doesn't have to be concerned for catalytic converters?
2. Since the just "Rotella T" also has a spark rating then does it have to have less ZDDP so as not to cause problems with catalytic converters?
Just noticed these differences when I just changed oil in my '67 and used some of both to get to 5 qts.
Thanks

[William F.]

Re: Zinc in Rotella T

I talked to Shell and got answers to my questions. The T4 is the newer labeling and continues to have 1200 ppm ZN. It has no S rating since gas automobile manufactures lowered allowable limits of ZDDP from time "plain labeled" Rotella T " had an S as well as C rating and Shell did not want to lower its concentration at expense of sliding friction reducers to meet S specs;so, Rotella T4 has just the C ratings with continued 1200 ppm ZDDP. Still good. Hope this makes sense.

[Duke W.]

Re: Zinc in Rotella T

I've never purchased Rotella, and I don't know the difference between T and T4. As I said earlier in this thread, I find Shell's marketing designations confusing.

Remember that secondary categories are optional, and there are plenty of other brands to choose from. You can easily find spec sheets for most oil brands with a Web search. Some of the new CK-4s have reduced P concentration, and my understanding is that a newer boron-based anti-wear additive is added to make up the difference, but the spec sheets don't say anything about the boron concentration.

The important thing is that CK-4 is "fully backwards compatible" with prior C-categories, so they pass all the C-category tests including wear.

Duke

[Tony S.]

Re: Zinc in Rotella T

Thoughts on DRIVEN RACING OIL? The bottle reads ZDDP-fortified break-in oil. I don't see any ratings though anywhere on the front or back label?

[William F.]

Re: Zinc in Rotella T

It doesn't have an API rating. In past I have used the Driven 10W30 "hot rod oil", not racing version,, but it seems it's actually an Amzoil product. Think I'll just stick to a diesel oil such as Rotella T, which I also use . By the way, most say don't use a racing oil in a street driven car since oil requirements for racing are not what is needed or desired street driving.