Do we to add Zinc to an oil change ?

[Warren96]

I have always used Rotella, but they no longer list API SERVICE CJ

[DmaxMaverick]

I don't see any problem with it in older vehicles. Zinc was removed from recent oil formulations to protect late model emission systems.

[Robyn]

The Zinc is/was used to protect parts like flat tappet cams/lifters from failure...
The roller lifters used in the 6.2/6.5 are not a problem.

As Maverick mentioned...the removal of zinc was to protect emissions equipment.

A good quality diesel rated oil will be fine.

[Yukon6.2]

The red bottled STP had Zinc in it.
I still have a few bottles that i add to my old diesel's oil.

[JohnC]

This is a big concern in the Old Mercedes overhead cam flat tappet world. There are a number of additives available; google "ZDDP Additive". Until recently, the answer was to use Rotella T-6, but it sounds like maybe that's no longer the solution.

[Robyn]

Several manufacturers offer racing oils with the ZDDP package that is needed for flat tappet cams.

The roller lifters do not need the zinc to be happy campers...
Same pretty much holds true for bearings, rings and other components.

The zinc and other chemicals that make up the ZDDP package raise hell with the catalytic converters and with the government mandate that the emissions systems be able to last much longer than previous systems.....the additives were removed as they pollute the cat and KILL IT.

There are Zinc additives available...but too much is not good either.....

I have explored this arena...as it applies to the fresh engine I am building for the Snow cat.

The only issue with the new oils are with older flat tappet cams.....

All 6.2/6.5 are roller lifters....not an issue.

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