ZDDP

[PHROG]

To me my 92 G/P is a "late model", so I have just recently become concerned as to it's need for ZDDP. Is the camshaft in the 3.1 V6 a flat tappet or roller lifter? My other vehicles range from 34-78 all w/flat tappets except the 34 is awaiting aZZ4 install w/rollers.

 

THANX, Roger

[jman093]

A 1992 is still a flat tappet. It went roller with the 3100 design in 1994. More ZDDP has never been needed in these engines though. Any quality modern oil is still perfectly fine.

[Psych0matt]

If it needs more of anything it's ZZTop

[Padgett]

Interesting. My '88 3800 LG3 has a roller cam and lifters. The LG3 also has a dual ring balancer.

[cutlassdude96]

Interesting. My '88 3800 LG3 has a roller cam and lifters. The LG3 also has a dual ring balancer.

 

your 3800 would be LN3

[Schurkey]

ZDDP is over-rated.  It's an effective anti-wear agent, but not the only one that's suitable.  The main force driving the use of ZDDP in motor oil is that it's cheap.

 

Stock engines don't need as much anti-wear/anti-scuff as modified engines based on the very low valve spring load.  As the valve springs get stiffer, the need for anti-wear additive increases--as does the need for properly-hardened cam lobes and lifter bottoms.  The influx of Communist Crap (soft cam cores, soft lifter bottoms) was the primary reason for so many cam failures beginning some years ago.