I wonder about this myself. But I stick by this, if you use good quality oil and change it often there is no really a need for additives. Actually I received a service bulletin from Honda ( since I work for an Acura dealer) regarding the use of additives. They state while it doesn't do any harm to your engine, it also dosn't really benefit as well. Just stick with a good oil and change it regularly, as I just mentioned before.
They go on to say that this also applies to any additives for all of the systems involved, be it fuel,oil,transmission etc,,,
The only advantage I can see is for high mileage engines that could use some help. For example STP oil treatment for maintaining some oil pressure.
Last edited by GT50; 12-27-2002 at 08:46 PM.