Blacknightz

if im seeing it right, there is a thin orange 'gasket' or sealer of some sort. U need to have an expert opened it up and place a new seal and he will also apply a grey sealent to seal it properly

NewKid

Do I have to get it done by a pro? I have taken transmissions out before...is it a seal or just some sealant? And what is the name of that seal then? I don't want to get ripped off by the dealership.

angelofragnarok

Just stopping in with an update. I had my fluid changed to MT-90, along with replacing the clutch (bad), master cylinder (bad), and slave cylinder (bad) and now the car grabs gears and drives better than ever! No grinds or hesitation between gears at any speed that I've tested.

Gingernator

I've had similar problems with mine. Real hard 1-2 shifts and grinding 4th gear, as i have mentioned in a couple of my other posts. Still no solid explanation...
https://www.rx8club.com/series-i-trouble-shooting-95/grinding-4th-gear-but-53-000-miles-222180/
https://www.rx8club.com/series-i-trouble-shooting-95/1-2-shift-difficulty-226753/

Evilnissan

Got my trans oil changed a few weeks ago before my motor blew and shifting has improved in smoothness but feel universly heavier in all gears.

2nd gear has always been iffy and the fluid change has improved feel and action when the trans is warm but now seems much worse when cold.

Should I try a different trans oil, Redline?

terrypk1

Hi People
I have been having problem when downshifting from 3rd to 2nd at higher speed (so i will be at 6000 RPM in second after downshifted).
It grinds...so after reading it up a bit, people seem to say that it's the synchro having problem.

Can you someone explain how it works and why it is causing the problem?
And
what I can do to fix it?

Thanks

Gingernator

It's either a bad sychronizer or a bad shift fork. I've deducted that my 4th gear's shift fork has somehow become damaged and doesn't function fully. Your's might be the same, although if you are rev matching perfectly on the down shift then that might be the synchro. If it is either, it'll most likely be cheaper to just get a new transmission considering labor costs of dismantling a transmission, repairing it, and reassembling it. OR, it might simply be a matter of you not correctly rev matching. Try double clutching into second, i.e. be going in 3rd, pop it into neutral, take out the clutch, rev to like 7-8K, then clutch in and shift into 2nd. Worked for me when I was learning to drive a manual. 2 main options: live with it, or fork over the dough for a new (or used) tranny.

Gingernator

Mine has the same issue. It seems as though its that "Friction Modifier" BS that they put in your oil. If you let the car warm up first to like the second dash, then drive, it makes it MUCH smoother. Honestly, I'd switch to Redline without any friction modifier in it.

syre2004

I know this is an old thread, but all the more reason to post this. I started getting a 2nd gear grind in my 04 rx8. I replaced my tranny fluid with amsoil 75w-90 first, still had the problem, then I used that royal purple 75w-90 and the grind actually got worse, so I switched out to the REDLINE MT-90 and no grind at all and every gear now feels like new. Both the Amsoil and the Royal Purple where GL5 and the REDLINE MT90 is GL4,, so maybe that was the problem all along. Either way, my 2nd gear no longer grinds and I am a happy camper.

Gingernator

There you go! REDLINE fixes all your tranny problems!
Transmission case cracked? Add some REDLINE!

syre2004

Tranny cracked? Come on. All i am saying for a normal driver the redline really helped. and took the grind away, for how long we will see, but it definitely helped my particular situation.

Gingernator

I was exaggerating

mikethecripple

right ive looked through 32 pages and i didnt see my problem... ive just sold my SZ-R JZA80 supra with the getrag gearbox so i know what noises to expect with a heavy duty gearbox. but the one in my '8 type s has what could be a buggered bearing (possibly on the lay shaft) well it sounds incredibly rumbly when the clutch is engaged and it disappears when the clutch is disengaged... also when in 1st through 4th and 6th gears the noise is present but not in 5th (which im going to assume is 1:1 ratio? like my supra was) this has lead me to believe that the problem exists on my lay shaft if its anywhere. my getrag made a similar noise (not quite as bad but it was still there) so i was wondering is this a normal noise?

Gingernator

Is it like a wrirrrrrrrrrrrrr with a tiny bit of shuddering? Mine does the exact same thing. And 5th is 1:1. But I'm not sure if its really a problem. There might be a bad layshaft bearing but i think that since the lay shaft is mounted to the transmission case itself (through use of tapered thrust bearings most likely), then I think its just the rotational energy being transferred from the lay shaft to the case and in turn the rest of the car. And you wouldn't really notice it when you're moving since all the other road noises and sounds.

Gingernator

Go here:
https://www.rx8club.com/series-i-trouble-shooting-95/2004-rx-8-issues-data-poll-43673/

MongoRX

iTrader: (1)

+1 More beleiver for Redline MT-90. Swapped fluids today and it seems to have smoothed everything out and it doesn't grind in 2nd or 4th quite so much. its the first day but everything seems to be better. Say 90% better.

StealthTL

iTrader: (1)

I found MT-90 a bit stiff, a little heavy - I mixed in about 1/4 to 1/3 of Redline MTL which is a lot thinner.

Have used that mix for the last eight years, lovin it!

DemonRex

Hi guys, I picked up an 06 M/T sport a week ago, got the plate on it Wednesday and started driving it. Last night on my way home she started acting extremely strange, too high in the rpm range for the road speed.. things like that, me being able to hit the accelerator in 6th, watch the RPM jump like crazy and see no reflection of that in my road speed. Then, I stopped at a stop sign, and she wouldnt get above 20 mph in any gear, so I pulled over, and when I tried to pull back onto the road, I had exactly 0 clutch engagement of any kind.... ANY ideas?!?!

I know there is a really long thread, and it's a pain when I'm sure the answer must be here somewhere... but I'm freaking out... please help?

Shamblerock

I am no expert, but if the engine revs and the car don't move appropriately in the manner you describe, sounds like a fried clutch... A new one installed should be $750 or less.... If it grabs when its cold and then doesn't grab when its hot, the clutch is completely worn out. Just my 2 cents worth.

Gingernator

Either a bad clutch or a bad clutch slave cylinder, either way will cost a little dough, but that's sort of implied with an RX-8 :P

Evil Grin

I also have a '04, and I changed my tran fluid to redline mt-90 about 5k miles ago. It was like you said silky smooth, but now I can feel it wanting to grind especially 2nd to 3rd and 4th to 5th. I've read several praises for motorcraft fluids with our trans, so I might go that direction here soon.

yeyo_racing

You guys might want to try Amsoil Synthetic Manual Transmission and Transaxle
Gear Lube 75W-90 API GL-4. The Amsoil folks call it MTG.

http://www.amsoil.com/storefront/mtg.aspx


I bought my 8 last year and the previous owner changed both the trans and diff fluid to RP. The car ran fine for a couple of months then started to develop a grind in 4th @ about 4500 RPMs. Changed the trans and diff oil to Amsoil and grinding was gone. Also noticed smother shifting while cold.

just my 2 cents.

Blacknightz

Coolz.... thanks!

gorx8

changed the trans...meaning changing the whole transmission? under warranty or you paid outa pocket?

im buying one, tested 5 rx8 now. 2 outa 5 have grindings...im concerned.

LeDonneza

Second gear also grinds at high RPM. I only have 48,000 miles on it.