[TR] somewhat off topic

[Randall]

> started and run for 
> a few minutes
> every other week or so.

That's a terrible thing to do to an old engine.  It would be kinder to put the battery on a float charger and not start the engine
unless you are going to drive far enough to get the oil hot.

> how often should I change the oil?  typically it gets changed 
> every year or so.

I believe GM's recommendation was 6 months.

> I am wondering if I am wasting my money putting synthetic in it.

Perhaps so, but that's what I would do.

>  I do believe I should be sure that the oil I use has zddp.

Contrary to popular opinion, all quality motor oils have ZDDP in them.  The debate is all about the reduced levels in the most
recent "emission" oils.  ZDDP only gets consumed when thee is actual metal-to-metal contact (the oil film gets squeezed out).  So,
since you are hitting the age limit instead of the mileage limit, I don't see any reason to use an old fashioned oil with elevated
ZDDP.

Randall