Any suggestions who would be able to do a good job assembling my gearbox in Melbourne or wider Victoria.

Mark

Know just the man in Qld.May even have a few spare parts.
Let me know if you get fully stumped.

Quote:When it comes to the 5 speed 56A gearboxes there is no such thing as 'option 2'

During 1971 & '72 the factory produced two competition versions of the four speed & these were the close ratio 'option 1' and the ultra close ratio 'option 2'[Four speeds]

During 1973 the 5 speed became an option in the GX model & this was simply known as the 5 speed option gearbox. It could also be refered to as the standard 5 speed gearbox. The designation for this box is 5FW56A from memory.
The car that came with this gearbox is commonly refered to as the GX5 these days.

Soon after this the close ratio competition version became available &, like the two four speeds that it replaced, it was available only through the competition department as either a conversion kit of parts for your standard 5 speed, or as a whole transmission assembly.
These were known as the 5FC56A or more commonly as the 'option 1' five speed.

Quote:
Do you have a whole differential, or a whole rear axle assembly?
If you have just the whole diff, as you say, then either count the teeth & do a little maths, or alternately, roll the ring gear around untill you can read the numbers that will be stamped into the edge of the ring gear near the teeth. These numbers will be the pinion & ring gear tooth count & you still need to do a little maths.

Quote:

I have a close ratio 4 speed with the 2.86:1 first gear but I haven’t heard previously of another 4 speed close ratio. Do you have any idea what the ratios were?
input 1st 2nd 3rd 4th
Close 4 29 30 25 23 1
Layshaft 19 16 20 26 1
Ratio 1.526316 2.861842 1.907895 1.350202 1


It seems that the normal `box in a B110 (1200) was a 56A (common 4 speed or rarer 5 speed) but what was the normal `box in a B10 (1000). There are several 3 and 4 speeds in my shed from B10s but I am not at home at the moment.

Was the close ratio 4 speed a 56A? Logically yes, but I have the gears in a casing that came from B10 (1000) so maybe that's a 56A also.

Mark

The standard gearbox in B10 cars was the 56 series in either 3 speed column shift, 3RW56 from memory, or 4 speed floor shift, 4FW56
R= Remote shift [Column shift]
F= Floor shift
W= Wide ratio

The 56A gearbox was a 'strengthened' version of the 56 series so there is no point in going for the earlier gearbox.

The four speed Option 1 & Option 2 gearboxes were 56 series [not 56A] & these can be identified by the front cover plate over the front support bearing for the cluster. You would need to look into the bellhousing to see it.

The 56A series used a smaller diameter closed end Torrington needle roller race for this task & it was pressed into the front of the gearcase, so there will be no cover plate held in by a few bolts.
From what I can gather the 56 series four speed was the standard issue for most, if not all of 1200 passenger car production in Japan.
The 56A four speed was used in the 120Y [B210] but may well have appeared toward the end of 1200 production in 1973.
The 'standard' 5 speed was always a 56A version & as we know, was available in the latter part of 1973 as an option in 1200 GX models.

The gear ratios are as follows

Standard 56A four speed
1st 3.757
2nd 2.169
3rd 1.404
4th 1.000

Option 1 [close ratio]
1st 2.862
2nd 1.908 [or 1.909, both specs from the same factory reference source]
3rd 1.350
4th 1.000

Option 2 [ultra close ratio]
1st 2.169
2nd 1.593
3rd 1.233
4th 1.000

56A five speed [5FW56A]
1st 3.757
2nd 2.374
3rd 1.659
4th 1.254
5th 1.000

56A five speed 'Option 1' [5FC56A]
1st 2.676
2nd 1.691
3rd 1.398
4th 1.182
5th 1.000

Four speed gear tooth count
Option 1 [close ratio] Option 2 [ultra close ratio] quoted in brackets.

Input shaft [Main Drive gear] 19 teeth [19]
constant mesh on cluster.[Counter drive gear] 29 teeth [29]

1st main gear [on main shaft] 30 teeth [27]
1st counter gear [on cluster] 16 teeth [19]

2nd main gear [on main shaft] 25 teeth [24]
2nd counter gear [on cluster] 20 teeth [23]

3rd main gear [on main shaft] 23 teeth [21]
3rd counter gear [on cluster] 31 teeth [31]

Option 1 five speed tooth count details are available on request.
I do not have the details for the standard 5 speed unfortunately.

Source material ........................
Datsun B110 Competition Tune Up manual
Nissan Motor Co.
Tokyo, Japan.
1974

Hopefully at least some of what you are looking for can be found here.

I have a Nissan B10-T KB10 Sports Option Parts list dated 1969 12 that lists the Option 1 4 speed close ratio (2.862 first), so that option might have been available earlier than 1970 and the B110.

Any idea what the “-T” means in B10-T?

I am still trying to work out what gears I have for a 5 speed, the counts are:
1st gear 32, layshaft 18.
2nd gear 28, layshaft 23.
3rd gear 25, layshaft 26.
4th gear 22, layshaft 29.

So yes please for the gear count on the Option 1 CR (2.676 first) box.

The sports option list includes suspension parts (springs shockers and bushes), brake parts (shoes, cylinders and lines), motor parts (head, cam valves, pistons, pulleys and a baffled sump), oil cooling gear, electrical (coil, dissy, alternator etc), exhaust, side draught carbies and manifold, LSD and 3 ratios (4.111, 4.375 and 4.625), roll bar (back half only), electric fuel pump, steering wheel, head light covers. 4 point seat belts, foot rest, mud flaps and even rear steps and handles so the poor navigator can stand on the back and help with pushing and traction in bad conditions!

Mark

I finally got a competent count on the teeth on the 56A five speed [5FW56A] (Barry counted them).

1st 32/13 = 3.757
2nd 28/18 = 2.374
3rd 25/23 = 1.659
4th 22/13 = 1.291
5th = 1

They are the ratios I want so it's go with the new gearbox, maybe a 6 speed is the next challenge, an overdrive for long transports would be good.

Mark

I have a 1200GX 5 speed gearbox (5FW56A) to go in the B10 but the nylon teeth on the speedo drive have been stripped.

Will the speedo drive from a B10/B110 4 speed (4FW56) fit? If so, will it give me the correct (well as close as any) speed reading?

Mark

I now have the 56A 5 speed ready to fit but I am not sure of what parts I need and what modifications are required.

Maybe I am best off paying someone who knows what to do and can do a sympathetic job (keep the hammer away from the transmission tunnel). Anyone interested?

Greater Melbourne or Victoria.

Mark

We have learned more about the transmissions in the last 3 months.

That is the most common F5C56A, the Datsun 1200 GX-5 box. C refers to servo style synchro, and W for Warner (Borg-Warner) style synchros. The 56 5-speed only came with C type.




See 56-Series Transmission, section F5C56A.


You won't see all the 4-speed OPTION ratios in your B10 catalog as there were more added during B110 time frame.


There were three different F5C56A gearsets:
F5C56A GX5
1st 3.757
2nd 2.374
3rd 1.659
4th 1.254
5th 1
Rev 4.04

Nissan Competition OPT 1
3rd 1.291
Nissan Part number 32010-H7251P

Nissan Competition OPT 2
Close Ratio
1st 2.676
2nd 1.691
3rd 1.398
4th 1.181
5th 1
Rev 2.877
Nissan Part Number 32010-H7220N

See 5-Speeds section Ratios at the end.