I have a 2006 MCS with the 6speed manual tranny, non LSD with 114k on the clock. I changed the transmission oil 2 weeks ago for the first time. The original oil was actually lighter in color then I thought it would be with minimal particulate in it and when I say minimal I mean close to nothing. Tonight I decided to check the level of the transmission fluid which was dead on. I noticed the color of the oil immediately which is why I am posting this. I used the Royal Purple Synchromax as the replacement oil.

Take a look at the picture and give me your opinion. I know what I'm thinking.

On the left is the RP from the transmission. On the Right is straight out of the bottle. 2 weeks?

I have no complaints as the transmission shifts better then ever after the oil change.

 

it only means the transmission was really dirty, you may want to flush it or wash it with oil several times, using a filter to "clean" the oil comes out, and then put them back, do it couple of time, that's what I planned to do.

 

Wow...considering that the oil that came out the FIRST time was almost clean, that is a fast change!!
On thing...was the car LEVEL when you refilled/checked the oil level? Doing it on a ramp or incline, like only front half on jack stands my result in over/underfilling due to the angle.

 

Don't worry and enjoy your car.
Oil color is meaningless. We like to think the color has some meaning because that is what we were told for so long. We were also told to change oil every 3,000 miles because it sold oil.
Oil has changed a lot in the last few years, for the better.
On the Miata site I frequent (miata.net) there is an professional oil engineer, (tribologist ?) who is always debunking the color issue. Color of any oil is almost meaningless.
If the car shifts well and the level is good just drive and enjoy.

 

Some oils change colors after they heat cycle. the color is meaningless it just means the additives in the royal purple that help to clean are doing their job correctly