you are somewhat confused it seems.....no need to add any additives.....it's not bad to change from reg oil to syth then back....why would you use reg oil unless you have a leak?.....the filter is the most important thing using those cheap *** fram and the like.....with today overdrive transmissions 100k on any type oil is the norm now....if you use syth 150k should be no problem what so ever.....the car manufactures have this 100k burnt in our brain that the car is wore out..why?.. they want you in a new car or they go broke ....

 

bwahahahahahaha... actually the local lube shops

 

I change my own oil roughly every 3k miles just for peace of mind

 

I knew you didn't

 

It is a bad idea switching because your engine might not be able to cope with the degradation in lubrication. By degradation i mean the wear tolerances that an engine develops based on the oil that it's using. Thicker mineral oils mean thicker layers of oil coating the moving parts (by microns though). Switching to a thinner synthetic oil can cause piston rings to leak and in some rare cases, piston slap or crank vibration. & If you've been driving around with mineral oil in your engine for years, don't switch to synthetic oil without preparation. Synthetic oils have been known to dislodge the baked-on deposits from mineral oils and leave them floating around your engine...not good. When switching to synthetic from mineral it is a good idea to use a flushing oil first.

 

I use Mobile 1 on mine..it ussually cost me around 45 bucks at autozone for everything and heck..i ussually change my oil every 2 months or so and i hardly drive it.But all ive gota say is..a clean engine it a happy engine

 

all oils have detergents to help clean the engine...lessing any deposits......that's why a quality filter is a must.....if you have clean oil after say 1k miles than your oil isn't working.....as for the tolorances that is mute after the engine is started and new oil is circulated. as for syth. being thinner is just not true..it carries the same wt but doesn't thicken like reg oil does. when cold.a great benefit in start up

 

first of all, oil companies recommending service at three months has nothing to do with oil and gas mixing in the combustion chamber. if you have oil in your combustion chamber, your piston rings are bad and that's a very bad thing. (it means you'll need a rebuild, or at least new rings)

and when storing a car, it's best to DRAIN all the fluids, not change them.

you need to find some new sources of information.

 

I always do it every 3k. I use Mobil 1 so maybe 5k is ok. I always thought 3k no matter if it's synthetic or not.

 

I am aware of the oils having detergents & that black oil means not that the oil is bad, but has cleaned the engine aswell as good filters being a must, mabey even magnets on the filter to catch some pieces of metal the filter misses.
My information on oil is coming from auto class in a section on oils & here.
Have a look C.