mrrisk

Great write up! This is premium quality stuff.

racinjayson

Ok, so I had my reverse shifting fork break on my 6spd and I was having a hard time trying to find parts for this transmission. Turns out the 99 to 05 Mazda Miata 6spd trans is made by the same company(Aisin AZ6), so I took a chance and purchased one that was a core for parts only. Here is the low down, the input shaft for the two are different and the main shaft as well as the bell housing and tail-shaft housing. The gears are different ratio's but the same as in they'll work in the nissan trans. All the syncro's, shift forks, bearings, secondary main shaft and complete center section including the case itself are exactly the same. So if you looking for parts to rebuild your nissan trans in the U.S., you can get most everything you need out of the mazda and you can get parts online from Jim Ellis Mazda with a complete parts diagram breakdown. Hope this is of some help to anyone in need of some rebuild parts, thanks.

TheRealSy90

The Aisin AZ6 is in a ton of vehicles:

Altezza AS200 & RS200
Lexus IS300
Toyota "86"
Scion FRS
Subaru BRZ
Mazda MX-5
Mazda RX-8
Nissan S15

Has anyone tried the "circlip fix" on their s15 trans? There's a company in Australia that does the fix or can send the parts pre-done. Apparently it's the main weak point that causes the strength issues on these trans and once the revised part is installed they hold up to a lot more power/torque.

__________________

racinjayson

Way to go Wikipedia man, none of those are the same as the Silvia except the miata trans. I searched them all and they have the same designator (AZ6) they are not even close to the silvia.

TheRealSy90

How are they not the same exactly? You yourself noted the differences between the Miata and Silvia trans. So those aren’t “the same” either.
I know for a fact the Altezza/IS300 trans is just as similar as the Miata trans is. With the same differences as well. Again, same for all those other vehicles. Aside from bellhousings, gear ratios, and the odd sensor here or there, other internals are effectively the same.


Sent from my iPhone using Tapatalk

__________________

racinjayson

You're missing the point the altezza is a Japanese car, I'm giving information about a U.S. based model that you can get parts for in the U.S. not Japan.

TheRealSy90

Ok 5 of those 6 are american lol.

__________________

racinjayson

And those five are not the same or are not readily available or cost a fortune, dude don't you think I already went down this road before I posted, give me a break.

afishysilvia

So at this point what do you need then? I’m running a J160 in my Altezza Beams and have a spare sitting in my garage. I’m not looking to sell but do you need photos of something?

__________________
Dont be a pussy...Leave your name

racinjayson

Jason Shaha, and I don't need anything, I used a Mazda miata six speed transmission and got the shift fork and a few synchro's, back together and running.

afishysilvia

No need for introductions, I am just clarifying what’s needed here before this thread turns to shit. Glad you resolved your problem and thanks for the input.

__________________
Dont be a pussy...Leave your name

[240sx]

Non-pussy confirmed.

Sent from my SM-G970U using Tapatalk

slow_sr20

Does anyone running a Dakota Digital SGI 5 know roughly what their configured settings are? I’m setting it up to use the abs sensor on the s14 diff through SGI5 to 95 s14 SE cluster.

dwnshft2drft

Lowest setting 2.50 and still off by 10% to 20% at actual speed 65 mph - speedometer reads 80mph. I think I’m doing it wrong?

97 kouki cluster
S15 abs diff sensor

afishysilvia

This is gold lol.

__________________
Dont be a pussy...Leave your name

TheRealSy90

Anyways, this is what I was talking about. Neat Gearboxes in AU offers the fixed gear shaft that fixes the main weak point in the az6 trans. Oh what do you know it works in ALL of those chassis I posted




Sent from my iPhone using Tapatalk

__________________

dwnshft2drft

CRIKEY mate!

LoSt180

Has anyone successfully used the S15 ABS controller to get a functioning speedo in an S14? Which wire in the cluster do you connect the ABS speedo output to? The S14 VSS is 2 wires (R/Y & R), but the S15 output is only 1 wire.

RalliartRsX

Just saw a S15 6 speed with S15 diff, clutch and shift mechanism for 2200!??!!?

I am pretty sure the glss S15 gearbox is worth as much as my #2 pencil.......with no lead

Kingtal0n

I Know someone local, tuned the car, 440rwhp through that original six speed for almost 20 years now. So I don't count them all out of the game.

RalliartRsX

Whp is not what breaks gearboxes. Its sticky tires/grip, digs and torque.....

The s15 gears are physically smaller to allow the gearstack to fit in the exact same space of the larger gearstack of the 5 speed.

Dont doubt ya king.. but a single notional data point doesnt properly categorize the actual physically smaller size of the gearstack or the well documented failures

Also intended use and vehicle weight has a major affect on how long they last.....that and which Japanese glass company made the gearstack that day hahahahah

TheRealSy90

Yeah that?s my post. I priced it according to what I see s15 spec r transmissions for sale for on eBay, as well as the complete differential which I only found one other for sale.

Again, Neat gearboxes has posted info on what the main fault with the transmission is and what usually makes them fail. Plus tons of people have ran these transmissions without failure. Everyone assumes they just shipped every s15 out the factory with a broken transmission .

For a street car that someone wants a nice 6 speed trans setup where everything bolts with in without any adapter stuff, it?s perfect.

Also my asking price was 2200 or best offer.

Every trans on eBay is 1400 and 900 for the one diff that?s on there..




Sent from my iPhone using Tapatalk

__________________

TheRealSy90

I would hope that someone wouldn't be dumb enough to be drag racing on the transmission. For what it's worth people break s13/14 transmissions all the time with stock/bolt on sr20's. They're all "weak". This transmission isn't intended for a damn racecar.




Sent from my iPhone using Tapatalk

__________________

LoSt180

Instead of parroting 18 year old flawed arguments about smaller gears, here's some useful info:

The rear output seal to the driveshaft is larger than the common S13/S14 seal. Vendors told me it was a JDM part that would have to come in from Japan.

Turns out the FRS/BRZ output seal is exactly the same size and readily available at your favorite parts stores/websites.

The shifter housing gasket is still a JDM only part, so waiting on that thing.





Also, the aluminum drain/fill washers can use Toyota part as well: 90430-A0003

LoSt180

No one really answered my speedo question. So, looking over the Nismo catalog I saw that they offered a VSS "kit" consisting of a snap ring and ball, but no info on the gear. Found some old threads and ordered an S14 gear. Needed to dremel out the middle a bit since the S15 output shaft is 3mm larger than the 5 speed. Crossing fingers this works when i finish everything up.

Parts:
32228-RRS50 - Snap Ring
32720-RRS50 - ball
32701-E9800 - gear

dwnshft2drft

I did the same thing definitely highly recommend than inaccurate dakota digital.

LoSt180

What final drive ratio are you using? Mainly wondering how far off my speedo will be if I change to 3.69 gears vs the stock 4.08.

dwnshft2drft

Right now its 4.08 diff, s14 cluster and, speedo. I?d say 2-3% faster maybe because I?m running larger diameter wheels sets.

Before I had the dakota wired with the abs diff sensor it was 20% faster. My oil change intervals went pretty quick lol

Let me know how that 3.69 works. I have the s15 diff waiting to install.

TheRealSy90

That's weird that they don't sell a gear for the s15 trans VSS kit.

__________________

LoSt180

Dude, tell me about it. Apparently they have gears available, but I have no idea how to get ahold of Nismo Japan to ask. The guys at Nismo USA don't know. My guess is they have different gears to match up with final drive ratios. Would be better if they just made a part number list and let us order that way.