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Sentra 4-spd & 5-spd swap

Posted: Mon Jul 07, 2008 1:11 pm
by asavage
Are the gasser and diesel transaxles interchangeable?

Are there difficulties swapping the 4-spd & 5-spd transaxles?

Posted: Tue Jul 08, 2008 5:24 am
by davehoos
you need a CA gear box to fit a CD engine if you cant find a 5 speed,basically come in 2 main sizes.
type 30 and 31.no 4 speed listed in 1985 on SDS.
i have made gearboxes up from 2 halves but both had same internal parts.

B11/N12 3.789:1 [europe option 4.056:1]
B12/N13 CD17 uses a 3.7 final drive.RS5F30A
3.333:1 first gear 0.75:1 over drive.
CD 20 trans from N14 AD van etc may ce a good donor but a bluebird-primera-stanza should be a bigger trans with bigger hydrolic clutch.if you replace chutch pedal/box etc most nissan have the master cyl mounts.

things to check
the starter motor mounting.
there are several types of starter mounting,the top bolt is the same[normally] and the lower bolt can be in different possitions.i had to drill a thread starter motor to suit.

the block flange mounting and clutch should be the same and gearstick localation--cv joint splines might be different,need to swap shafts or diff center.

Posted: Tue Jul 08, 2008 7:19 am
by asavage
davehoos wrote:you need a CA gear box to fit a CD engine if you cant find a 5 speed . . .
I think you're assuming that I know more than I do. Talk to me like I'm a baby, Dave: what is a "CA gear box"? Is this a transmission that mates to a certain gasser engine (seems like I've heard of a CA-something Nissan engine).
type 30 and 31. no 4 speed listed in 1985 on SDS.
What is an "SDS"?
i have made gearboxes up from 2 halves but both had same internal parts.
That's what I've done to replace the FS5W71b trans in a 720 PU: use the front case half ("bellhousing") from the SD trans, onto the gears-n-guts and rear case half of a gasser's trans.
CD 20 trans from N14 AD van etc may ce a good donor . . .
No CD20 in North America, so not really an option here . . .
but a bluebird-primera-stanza should be a bigger trans with bigger hydrolic clutch.
We do have Stanzas here. Will the "bellhousing" (front case half) of my existing CD17 4-spd mate to a Stanza 5-spd?
if you replace chutch pedal/box etc most nissan have the master cyl mounts.
I don't usually mind a clutch cable setup. This one seems grabby, but then I have a completely toasted rear engine mount (on backorder).

Posted: Wed Jul 09, 2008 4:13 am
by davehoos
find a 5 speed sentra-it should be available as standard in the later models
asavage wrote:
davehoos wrote:you need a CA gear box to fit a CD engine if you cant find a 5 speed . . .
Dave: what is a "CA gear box"? Is this a transmission that mates to a certain CA gasser engine
CD ENGINE IS BASED ON THE C family ENGINE BLOCK.the CA is the petrol/LPG version and the basis for the LE16/18 GM-holden family 2[opel]engine made for the nissan N13--the gearbox/block flange in FWD trim is the same design as the diesel version.american gas sentra has a smaller E or the later GA engine.

The CD20 is allmost a copy of the gas engine.CA range of engines[16-18-20] SOHC-DOHC and both with turbo verisions-also low compression and carby versions also LPG factory engines.LE16/18 engine block shares measurments with the CA range but uses the CYL head and water pump of the opel engine.
type 30 and 31. no 4 speed listed in 1985 on SDS.
What is an "SDS"?
Service Data and Specification.
these are printed every year.australian books dont inc USA-or south america.they only cover vehicles that come via japan--they dont include models made in australia-tiawan etc etc.they include southafrica and some minor markets with the specs of parts imported to assemble their version.these books include teeth counts for gearboxes for ID purposes as there are many options in some markets.
i have made gearboxes up from 2 halves but both had same internal parts.
Nissan gear boxes FWD in this size car are normally a type 30,diesel and performance models are type 31.parts normally these 2 types dont interchange.i would expect the same type boxes to be interchanged.my experience is changing damaged casings and fitting visco LSD.

the 5th gear is an addon to the 4 speed but it is within the casting,you have to change the outer casting shafts geats selectors and might have to change the crown wheel.

We do have Stanzas here. Will the "bellhousing" (front case half) of my existing CD17 4-spd mate to a Stanza 5-spd?
i have a stanza workshop manual.it covers europes small engine models with small cable clutch gearboxes-at the end it has USA updates that show it has the bigger gearbox.its hard to work out as canada is different to california etc.

there is no reason a larger car box wont fit in a small car.this is a common conversion here.importers bring these in a dump the boxes.

also another donor is the KN13 targa coupe sold in USA in aust its called EXA but in USA it might be NX or pulsar im not certian.these cars have a range of sporty gearboxes inc LSD.here they are 1.6 and 1.8 DOHC but in germany they come with small carby E and GA ser engines like in japan. these gearboxes fit in a sentra and the CA type will fit on to the engine.
This one seems grabby, but then I have a completely toasted rear engine mount (on backorder).
the pulsar here is grabby its a lot to do with the clutch plate.mounts have to be good to stop the whipping.ive had drame with the thrust bearing sticking they often fowl with sand.

Posted: Wed Jul 16, 2008 8:04 pm
by asavage
davehoos wrote:type 30 and 31. no 4 speed listed in 1985 on SDS.

Nissan gear boxes FWD in this size car are normally a type 30,diesel and performance models are type 31.parts normally these 2 types dont interchange.i would expect the same type boxes to be interchanged.my experience is changing damaged casings and fitting visco LSD.
According to the data plate at the firewall, I have the 30 ("RN4F30A").

Image

Posted: Wed Jul 16, 2008 9:20 pm
by leadpaw
mine is also a RN4F30A gearbox. According to the Fsm the E16 b11 has an RS5F30A.

Posted: Thu Jul 17, 2008 3:49 am
by davehoos
diff ratio for your cd17 is 3.7:1
teeth count for 4 and 5 speed with 3.33:1 first gear.
you have to measure the distance between crownwheel and output shaft.
if swaping casings.i think they would be similar.

1986 is the oldest manual I go --N12 type 30 5 speed [pulsar exa sunny]
E15ET 3.550:1 71/20 teeth
cd17 3.789:1 72/19

E15 3.5 4.0 option except europe.
E13 3.8:1 4.0 option
E10 4.4:1-- 4 speed

B12 E13 4.3:1 74/17 teeth
CD17 3.7:1
E15/E16 have type 31 with 4.1 and 4.3 ratio.

Posted: Mon Jul 21, 2008 9:14 pm
by asavage
According to the 1984 FSM, the CD17 diff ratio is 3.789:1 (vs 3.650:1 for the gasser).

The 4-spd and 5-spd have identical 1st gear ratio (3.333) and top gear ratio (0.733).

So, while the 5-spd does give another gear, it does not add a taller overdrive than the 4-spd. Only a 5-spd box in combination with the gasser final drive would be enough difference to warrant the work of swapping bits about.