Are you sure the RX-8 synchro's are not bronze?

I my time all Mazda Synchros' were bronze, I think now they put a Carbon (Grey/Black) Coating on the Rings, but, over time most of this wears off, this is why you see very dark transmission oil when you change or flush fluid.

The Carbon coating is to assist in "wearing in" of the transmission.

 

My error. They are bronze and that is why the sulphur in GL5 corrodes them . Good pickup Ash.

I have just placed an order for some parts from Onlinemazdaparts.com. They sell Redline MT90 for $US11.95 per 900ml. It is worthwhile ordering a set of pads or coils and throwing a couple of bottles of this on as well as it only costs an extra 3-4 dollars to ship it. Please see attached order form.

 

do you know you can't (well, not supposed to is probably the correct word) send oil via air? so hopefully it'll go through or otherwise it'll take the sea route

I always get my oils from Harold (www.performancelub.com) and whilst not as cheap, it saves the hassle of importing oils and you get it much faster.

 

bump.
Had the exact same problem, to at T. I changed my tranny oil to Mobil1 75W90 as instructed by an autoparts store (I know I'm an idiot). Didn't realize until after the grinding started that Mobil1 is a GL-5 oil. I stopped driving my 8 til I could get the Red Line MT90 (had to order online).
Changed the oil to Red Line. The grinding persists, however it's a lot better than it was before. Still grinds in the 3-4 shift above 6000 rpm (or from any gear to 4th, if the RPM is above 6k).
I'm guessing whatever damage is already done? Any pointers?

 

Never mind. It seems to have gone away finally. Successfully shifted 3-4 at 8000 rpm today with no problems. I'm so relieved, was getting really pissed off..

 

I am using that combo for years. I thought that should not be any secret ... they are the best!

 

haha you know correct. hehe

 

I think I must drive the car after all these time sitting in the garage. have not touch it since the Nationals???????!!!!

Training hard on my bicycle I suppose. I am so good at it like when I was mad with my RX8. I feel like I can beat anyone up a climb now, but like tracking my car doing hot laps and ATC... and high end ameature and local pro will give me reality check.

Very happy with my riding at the moment. I am so slim nowadays... sorry that I have not contributing to this forum or the .au forum like I use to. I only have 24 hour a day....

 

Ordered me some redline mt90 to replace my tranny fluid with. I only have about 2700 miles on the car but I usually get some "notchy" / "clicky" / "minor grind" when going from 1 - 2 at a moderate rpm. Dealer told me its "normal" but i figure a flush doesn't hurt.

 

/\ Agree...look in S2 you have to make sure tranny is warm to hot, yes I get a 2nd gear notch at times, can depend on RPM and temps.

As I have said many times these boxes take a long time to "wear in" and they LIKE regular OIL Changes, at least every 12K miles or 20K KMS...

DO this and you should get a good tranny life...not preaching guys...you already know this ..right.