The FD, 5th gear, rear end ratios, and you
Joined: Mar 2001
Posts: 31,857
Likes: 3,243
From: https://www2.mazda.com/en/100th/
Was anything else changed (upgraded) in the newer JDM trans?
I am going to order the 5th gear parts from http://www.amayama.com/ and was wondering are there any other transmission parts I should include when rebuilding?
Mazda R51217308 (BJ JP) - 99.38 USD, 1 items
Mazda R51317610B (BJ JP) - 158.11 USD, 1 items
I am going to order the 5th gear parts from http://www.amayama.com/ and was wondering are there any other transmission parts I should include when rebuilding?
Mazda R51217308 (BJ JP) - 99.38 USD, 1 items
Mazda R51317610B (BJ JP) - 158.11 USD, 1 items
There's a few bits and pieces changed in the 1-4 section of the box, syncros mainly from memory. Might have even mentioned the ones years ago, possibly part nos too...if that section of the box is working, I'd not worry though, upgrade if anything, is minimal.
Joined: Mar 2001
Posts: 31,857
Likes: 3,243
From: https://www2.mazda.com/en/100th/
From Mazda Motorsports:
R513-17-610B* GEAR,OVERTOP The regular price is $263.16
The sale price is $157.86
R513-17-308* GEAR,COUNTER The regular price is $144.95
The sale price is $86.95
To buy at these prices requires a membership with Mazda Motorsports.
Last edited by jkstill; Sep 7, 2015 at 09:49 AM.
Does anyone know if this is correct? Been a pain trying to acquire this .806 gear
Still seems to be some confusion, are you after .806 or .763?
For 16" and .806, I've got R507-17-308 and R507-17-610C
For .763 on 17s, R513-17-308 and R512-17-610B. There could be a change or a typo, although the export 5th, .719 did have 1 digit differences in the part prefix too.
For 16" and .806, I've got R507-17-308 and R507-17-610C
For .763 on 17s, R513-17-308 and R512-17-610B. There could be a change or a typo, although the export 5th, .719 did have 1 digit differences in the part prefix too.
Still seems to be some confusion, are you after .806 or .763?
For 16" and .806, I've got R507-17-308 and R507-17-610C
For .763 on 17s, R513-17-308 and R512-17-610B. There could be a change or a typo, although the export 5th, .719 did have 1 digit differences in the part prefix too.
For 16" and .806, I've got R507-17-308 and R507-17-610C
For .763 on 17s, R513-17-308 and R512-17-610B. There could be a change or a typo, although the export 5th, .719 did have 1 digit differences in the part prefix too.
Also running those through http://www.amayama.com they show replacements:
R507-17-308 ---> R508-17-308
R507-17-610C ---> R508-17-610C
Last edited by Brekyrself; Jan 20, 2016 at 04:43 PM. Reason: added info
I'm looking for the .806 5th gear. Perhaps I misunderstood what j9fd3s said earlier in the thread. He may have been referring to "lower" as the .716 ratio?
Also running those through http://www.amayama.com they show replacements:
R507-17-308 ---> R508-17-308
R507-17-610C ---> R508-17-610C
Also running those through http://www.amayama.com they show replacements:
R507-17-308 ---> R508-17-308
R507-17-610C ---> R508-17-610C
Don't know the reason for the change, they were the #s in 2001. Mazda has been sourcing gearbox stuff elsewhere in East Asia, so there's a possibility of substitution. The gear is used in some of the commercial range....
I'd call the .806 lower > normal terminology here at least....sometimes the fingers get ahead of us!
Don't know the reason for the change, they were the #s in 2001. Mazda has been sourcing gearbox stuff elsewhere in East Asia, so there's a possibility of substitution. The gear is used in some of the commercial range....
Don't know the reason for the change, they were the #s in 2001. Mazda has been sourcing gearbox stuff elsewhere in East Asia, so there's a possibility of substitution. The gear is used in some of the commercial range....
Unless you're changing the diff from a 4.1, it's all good.
I've put it somewhere here before, the 4.3 one is R507-17-400B if that swap has been done. For a 4.44, 4.77 or 5.125 you're on your own!
I've put it somewhere here before, the 4.3 one is R507-17-400B if that swap has been done. For a 4.44, 4.77 or 5.125 you're on your own!
Last question on this subject. If going from the 4.10 diff to the 3.90 diff, would the gear inside the auto trans be interchangeable with the gear in the manual trans so the speedometer is correct? If so I should be able to find that part number in the USDM parts book!
Thread Starter
Joined: Jan 2002
Posts: 15,626
Likes: 2,733
From: Pensacola, FL
There's no reason to change the gear in the speedometer. Find my thread on calibrating the speedo, it's easy to do and you can make your speedo GPS dead accurate quite easily.
Dale
Dale
Thanks again, you have helped clear this up significantly.
Last question on this subject. If going from the 4.10 diff to the 3.90 diff, would the gear inside the auto trans be interchangeable with the gear in the manual trans so the speedometer is correct? If so I should be able to find that part number in the USDM parts book!
Last question on this subject. If going from the 4.10 diff to the 3.90 diff, would the gear inside the auto trans be interchangeable with the gear in the manual trans so the speedometer is correct? If so I should be able to find that part number in the USDM parts book!
Drive gear inside the tranny on the output shaft is a different - and of course the sender. No idea of it's just a teeth count change, different internal or external diameter, yada, yada....so maybe easier to take Dale's advice on that one, especially with rolling diameter/tyre changes.
Joined: Mar 2001
Posts: 31,857
Likes: 3,243
From: https://www2.mazda.com/en/100th/
Mazda's part numbering system is on its face, pretty simple. the first 4 digits tell you the original application, for instance the R508 tells you its for an R type transmission, or it can be an FDxx part number, which is an FD, or an N3A1, which is an early FD engine. miata is NA01..
the next two numbers tell you what section or system the part is in, 17 is manual transmission, 16 is clutch, 15 is cooling system, etc etc
the next three numbers tell you what the part is, so 17-400 is a speedo drive, 15-200 is a radiator, and so on. if there are two parts, like a fender or a headlight, the bigger number goes on the left. for instance FD01-34-700 is a right front shock, for a 93 touring model.
the next letter is the "change code", theoretically when Mazda changes the part, they change this, sometimes the part gets updated, sometimes the supplier changes, hard to tell sometimes what changed. of course sometimes the front number changes and not the letter, we found an oil pump that went from CY01-14-100A to ZZJ1-14-100 and then back to CY01-14-100, so it can get murky.
if there are two more digits, it can be a color code, or a supplier code (in north america). so something like FD01-67-510A-J9 would be a yellow wiper nozzle for the right side of an FD.
the only reason the part number works in the US is because there was some other Mazda that was sold here with an R box and a .806 5th gear. the R box came in the T2, FD, and also the 929, MPV and B2600, among other things
the next two numbers tell you what section or system the part is in, 17 is manual transmission, 16 is clutch, 15 is cooling system, etc etc
the next three numbers tell you what the part is, so 17-400 is a speedo drive, 15-200 is a radiator, and so on. if there are two parts, like a fender or a headlight, the bigger number goes on the left. for instance FD01-34-700 is a right front shock, for a 93 touring model.
the next letter is the "change code", theoretically when Mazda changes the part, they change this, sometimes the part gets updated, sometimes the supplier changes, hard to tell sometimes what changed. of course sometimes the front number changes and not the letter, we found an oil pump that went from CY01-14-100A to ZZJ1-14-100 and then back to CY01-14-100, so it can get murky.
if there are two more digits, it can be a color code, or a supplier code (in north america). so something like FD01-67-510A-J9 would be a yellow wiper nozzle for the right side of an FD.
the only reason the part number works in the US is because there was some other Mazda that was sold here with an R box and a .806 5th gear. the R box came in the T2, FD, and also the 929, MPV and B2600, among other things
More than likely, the input shaft needle roller will be shot if the box has significant miles on it for one. Most of the rest is inspection during the job, unless you have syncro issues evident now and those can be pre-ordered.
Although a lot of places will reuse them, by rights, once you start using pullers on the bearings they should be replaced...which pretty much makes it cheaper to buy a low km import box....if you can put up with the lower 5th.
Although a lot of places will reuse them, by rights, once you start using pullers on the bearings they should be replaced...which pretty much makes it cheaper to buy a low km import box....if you can put up with the lower 5th.
Sorry to beat the dead horse here however there is still confusion on what part numbers are for the .806 gear set.
j9fd3s mentions the .806 came with the 17" wheels
https://www.rx7club.com/3rd-generati.../#post11942292
billyboy mentions the .806 came with the 16" wheels
https://www.rx7club.com/3rd-generati.../#post12017615
j9fd3s mentions the .806 came with the 17" wheels
https://www.rx7club.com/3rd-generati.../#post11942292
billyboy mentions the .806 came with the 16" wheels
https://www.rx7club.com/3rd-generati.../#post12017615
Seems to be a fair old while happening! 
This - in translate - might clear up confusion.....
Revolution Online Catalog / ??????5???????5????

This - in translate - might clear up confusion.....
Revolution Online Catalog / ??????5???????5????
FD 5th GEAR SHIFTING NOISE / GRINDING
Service bulletin # 001/94 Cat. J, issued 1/7/94, revised 1/27/94
Applies to vehicles with a Vin of JM1FD332*P0100001 through 210508
If grinding occurs when shifting to 5th gear, a 5th gear synchronizer ring, damaged by mis-shifting, may be the cause. To correct this concern, the shift select spindle has been modified to increase the accuracy of the shift pattern. They raised the spring force from 6.7 kg to 8.9 kg on the shift select spindle.
Replace shift select spindle with part# R503 17 550 and replace 5th gear synchronizer with part# W501 17 725B.
************************************************** ************************
As I have over 400 whp, i use the JDM .806 5th gear with the 3.909 auto trans dif gear.
Service bulletin # 001/94 Cat. J, issued 1/7/94, revised 1/27/94
Applies to vehicles with a Vin of JM1FD332*P0100001 through 210508
If grinding occurs when shifting to 5th gear, a 5th gear synchronizer ring, damaged by mis-shifting, may be the cause. To correct this concern, the shift select spindle has been modified to increase the accuracy of the shift pattern. They raised the spring force from 6.7 kg to 8.9 kg on the shift select spindle.
Replace shift select spindle with part# R503 17 550 and replace 5th gear synchronizer with part# W501 17 725B.
************************************************** ************************
As I have over 400 whp, i use the JDM .806 5th gear with the 3.909 auto trans dif gear.






