ok for the longest time i took my car to the dealership to get my oil changed and those morons over there put the wrong oil in my car and now that we have been putting the right oil in there the oil gets extremely dirty quick, do you think that because of them putting the wrong oil in there has done some damage to the engine or is it just the rotery engine that runs so dirty? by the way keep this in mind after 500 miles after an oil change the oil in my car is alot worse im my rx8 than in any of my other cars that have gone the full 3000 miles. any info you can give me will be greatly appreciated!

 

Don't forget, whenever the oil gets changed on the RX-8, there will still be a lot of old oil in the oil coolers. Do you have the 6 speed or automatic? 6 speed = 2 front oil coolers

 

How do you define dirty? Did you do an analysis for insoluble %, or a Total Base # test? Maybe a "Doctor Test" for sulfur compounds? Does dirty oil not lubricate as well as shiny new oil?

The oil coolers hold about 5 quarts of the old stuff, so it is reasonable that within 30 seconds, your oil will be pitch black, but "so what"?

S

 

well if the oil coolers hold up to 5 quarts of oil in there is there a way to change that oil to so there wont be so much build up of dirt and what ever else is in there.

 

many have though about this, short of pulling the front bumper off and disconecting the oul coolers and lines to let them drain....no there isnt an easy way, doing that would work, but it would turn the change into a big job. Also you would have to prime the lines with oil, otherwise when you start the car there would be a gap in oil pressure to the engine, that could be bad. Also you could get air bubbles traped in the coolers, also bad.

Not to mention it would turn it into an 8qt oil change.

If it really bugs you that much, change the oil, and then drive around to mix it in and change it again, it will clear out more of the old oil, and keep doing that if you want, till its all flush out, but that could be expensive.

I did a change to fully syn oil over a few hundred miles, I changed the oil with a semi-syn, then drove about 100 miles, and then again, and another 100, and then I changed to fully syn and drove about 100 and changed again with fully syn. Then in 2500 miles, I changed again with fully syn. The oil is still dark right after I put it in, but at least I know that its mostly syn/semisyn in there.