The spec is only for engine built after 1/1/2007 and has little to no benefit in older engines from all I can tell. Its the chemistry of the oil that is changing not neccessarily does it mean CJ4 is better oil for pre 1/1/07 engines.
The older spec oil will continue on the market, millions of vehicles for them. The CJ4 oil will likely cost more money for the higher end oils, i.e. synthetic's.
Amsoil will introduce their PAO based, CJ-4 rated, 5w-40 ("DEO") on 1 Oct, priced about the same as their 10w-40.
One of the main benefits that I see is that these CJ-4 rated oils will also be excellent for newer gas engines. Expect to see them as CJ-4/SM products for mixed fleet use.
The reduced amount of sulfated ash should have a beneficial effect on piston crown and groove deposits.
I was in the local Walmart today and notice that the Shell Rotella 15W-40 jugs they had there had a new design...as I suspected, when looking on the back at the specs, CJ-4 was listed.
So, CJ-4 oils have hit the shelves.
Me three. Rotella and Delo now CJ4 at the local Wally Worlds.
Phosphorus reduction isn't an alarming amount. This low SAPS formulation might actually be the preffered one to use in gasoline vehicles.
Was in Menards locally today getting insulation and walked through the oil aisle...they have gallon jugs of Shell Rotella T 10W-30 CJ-4 (and API SM) rated...same marketing design that's on the the gallon jugs of 15W-40 that were at Walmart.
I think I'll go back tomorrow and pick up a couple jugs, I think this ought to be a good oil for my moms car that has a coolant leak...I'd think a HDEO would be a "hardier" oil than a PCMO and would take running with coolant a little better.