Hey guys so my fourth gear is grinding at high rpm now... I recently just got a new motor from Mazda, I saw my engine pulled out as well as my whole tranny. Now I never had this grinding problem until the motor change. I'm assuming they replace my tranny oil when they pull it? Before I had just recently switched to a synthetic oil and I had no problems... Could the problem be Mazda putting an oem transmission oil? Or maybe not refilling the transmission oil if any spilled?

 

Which oil do you use?

I use Mobile one.

It could be your PPF.

Go back and tell them that you want the PPF to be aligned as gears are now grinding.

 

I had my mechanic switch my tranny oil to a synthetic several months back. I honestly don't remember what brand it was, but I haven't had any problems with it ever since. Now that I got my car back, while redlining today on the highway I had gear grinding in 4th only. Ppf? Is that the power plant frame? How can one tell if isn't properly aligned? I was thinking that when Mazda removed my driveshaft and tranmission they spilled some tranny oil and didn't replace it... So now my tranmission fluid is low and why it's grinding at high rpm in 4th? I'm going to take my car to my mechanic on Monday, I'll have him do a tranmission fluid swap and I'll tell him to check the ppf. I just don't understand how it could not be properly aligned, from pictures it just seems to be a few bolts holding it to the transmission?

My car problems are depressing me... Just gotta be positive.

Oh and another thing... Other than the grinding at high rpm, the transmission shifts flawlessly during regular shifting.

 

Somebody? Any experience in a situation like this? Could it be my transmission failing already, the timing just seems a bit odd.

 

Okay guys I'm back... Earlier this week I had my mechanic check out the transmission fluid, and he said it was full. He drove my car and said it felt good and it definitely wasn't my clutch. Obviously he didn't take it high into the rpm, my car drives perfectly fine normally. I told him about the PPF, and he said it could definitely be that and advised I should go back to Mazda. I think this will be my only option, as my 4th gear is still grinding, only thing that sucks is I gotta put my cat back on...

Here is a video of my 4th gear grinding. I'm trying to put it into 4th with the clutch pedal fully depressed.

https://www.dropbox.com/s/yfh5y4jkc1...728_221214.mp4

He also said if it was my PPF I would probably notice my shift ****/lever was maybe in a different position while in neutral, I honestly didn't remember as I didn't look at that. Here is a picture, as you can see my **** is leaning towards the left side while in neutral, is that normal? Is it supposed to be in the center?

https://www.dropbox.com/s/ypo2op5p8m...2022.15.58.jpg

 

Just to finish this thread...

My 4th gear synchro ended up grinding at all RPMs and went bad period. I don't know exactly what caused this to happen, I'll probably just guess it was the unforgiving aisin S1 transmission.

Long story short, I ended up buying a S2 transmission and exedy hyper single stage 3 clutch and lightweight flywheel from 550rwhrex locally. https://www.rx8club.com/se-sale-want...single-235353/

I finally just got my car back today after a long week... So far the S2 tranny and exedy clutch have been pretty awesome. I definitely feel a difference with the lightweight flywheel it accelerates much better, and the clutch will take a little bit of getting used to but it feels pretty nice when I step on it.

 

I started having the same problem after using Royal purple the oil was very dark . Changed to Redline and the problem disappeared.

 

s2 transmission and 4.444 final gear means driving a super slow car.
Instead of wasting money on a clutch you don't need you could have bought a nice ring and pinion set... well there's still time to do it!

 

Super slow how so?

I don't think I wasted my money. Like I said I bought the S2 tranny with around 13k miles and a used (but still good) exedy hyper clutch kit from a rx8club member, and I got them both for $1,500. This seems like a good deal to me.

The S2 tranny is a much more reliable trans compared to the aisin, and the S2 trans with 13k miles usually goes for $1.5k or more. Add a clutch kit that goes for over $1,000 new, I think it was a very good deal. I had everything installed at a Mazda dealer that gave me warehouse prices on parts and a lowered labor cost as well. I had everything installed for $700, that is including extra parts that I needed as well (throw out bearing, pilot bearing, automatic counter weight for LW flywheel, counterweight bolts, seals...).

Do you still think I wasted my money? For about $2.2k I got a better trans, clutch, and lightweight flywheel.