And based on developments over the past year, thats exactly how some felt the life and times of CJ-4 would likely play out. Many thought CJ-4 would be engineered to provide the same level of engine protection as CI-4 PLUS, and its only additional benefit would come in being an environmentally friendly product designed to enhance the usable life of aftertreatment devices on on-road heavy-duty diesels engines.

Well, following a meeting of HDEO movers, shakers and specification-makers at the end of January, the verdict is in. With its new tests defined and the limits essentially fixed for these tests, it looks like CJ-4 will offer a significant performance upgrade over its predecessor.

According to industry experts, CJ-4 will be engineered not only to provide enhanced performance for aftertreatment devices, but also will represent significant improvements over the CI-4 PLUS category in the areas of valvetrain wear control, soot handling, oil consumption, and protection for bearing and ring zone components. In addition, it will offer superior piston deposit control. This last issue is particularly relevant and important with modern diesel engine designs.

So the good news is that in spite of the naysayers and the nonbelievers, CJ-4 will provide wear protection and other performance characteristics superior to that seen with CI-4 PLUS. And unless something changes dramatically during the final leg of its race to market, CJ-4 will in fact offer a demonstrable performance upgrade. The bad news, however, is that the added wear protection, emissions-system compatibility and other benefits will come at a cost. Moreover, these costs may still present hurdles too high for CJ-4 to jump during its early years on the HDEO track.

The first hurdle is measured simply in the comparative price of a gallon of CJ-4 engine oil against that of CI-4 PLUS. Given the enhanced level of performance as well as the lubricant design constraints required by limits on sulfated ash, sulfur, and phosphorus, the outlook continues to be that CJ-4 will be a significantly more expensive product than CI-4 PLUS. In fact, according to most experts surveyed by Petroleum Trends International, CJ-4 could cost end users anywhere from 15 percent to 30 percent more. This premium equates to roughly $1.00 to $2.00 a gallon.

If all else were equal, this premium is really not too bad, considering the higher level of performance ones fleet could achieve by using CJ-4. And in addition to superior wear protection, operators may also enjoy the simplicity of a one-barrel solution for all their pre- and post-2007 engine needs. Sounds good, but all things are not equal and therein lies the second and likely higher hurdle CJ-4 must jump if it wants to place in the HDEO market race over the next year or two: oil drain intervals. Like it or not, many users will focus right in on CJ-4s total base number (TBN).

Based on what some formulators are saying, CJ-4 oils will likely have a TBN in the range of 8 to 9. This represents a significant drop from the 10 to 12 TBN typically seen with CI-4 PLUS. And when end-users see a drop like this, all their alarms about drain intervals are going to go off. This is because TBN is a measure of engine oils ability to neutralize the acidic byproducts of combustion. Theoretically, when the TBN drops, so does the drain interval. A drop in TBN like the one expected with a move to CJ-4 could mean a 20 percent to 25 percent shortening of the distance between drains.

Granted, one could argue that any decline in drain intervals associated with the use of CJ-4 will be offset by the soon-to-be-mandated use of ultra-low sulfur diesel fuel. But even if this is taken into account, one has to wonder what engine builders like Caterpillar know that the rest of us might not.

Based on the mutual exclusivity of Caterpillars new ECF-3 and potential ECF-2 specifications – the first for Cat engines dated 2007 and beyond, the latter for earlier models – one could be led to speculate that they (and maybe others) know more about future oil drain intervals for EPA-compliant hardware using lower-TBN CJ-4 lubricants than they have publicly disclosed. And if they do, there is a good chance some of the big brands in HDEO will be a big bust if the only horse they have in the race is API CJ-4.