Rb25 Box In Ceff

[Cubes]

Digging up a thread.

I picked up a S2 R33 Rb25DET gearbox recently.

The tailshaft. I've been told all I have to do is remove the rb20det yoke and have the rb25det yoke welded in; no shortening etc is required.

Adelaide tailshaft - $160 to remove and weld in the new yoke with balancing.

I compared my R32 gearbox mount and crossmember to the R33 S2 Rb25DEt gearbox mount and cross member.

The crossmembers are Identical and essentially the mounts are also. The R32 gearbox mount has its metal trimmed up where as the r33 mount is simply a piece of metal with its sides bent up.

For those who have done the rb25det gearbox in to the R32 how far out does the rb25det gearbox position the mount compared to the std gearbox? 20mm?

Pics attached of the 2 crossmembers and gearbox mounts. All measurements and heights are the same.

I haven't bolted the box up yet as I'm waiting for a clutch,

Fingers crossed the mount bolt up position is only out by 20mm or so as then I can redrill the gearbox mount holes on the gearbox and use the std crossmember and my near new mount without too much trouble.

I doubt I will be so lucky as no doubt others would have looked at this and would have let others on SAU know.

[Simon-S14]

Hey mate

are you 100% about not shortening the tailshaft at all? I had to chop my front section down 20 odd mm or so, the front section, from centre of the uni to the center of the uni was 350mm long after i finished with it, thats with the 25 yoke on too. FWIW i did it myself at work, using a laithe and tig welder.

Is your 32 a factory manual? if so you might get lucky with bolting the box up and all holes should line up, mine was factory auto and some other crossmember was used. 2 out of 4 holes line up, and i redrilled one side to get a third bolt in.. no drama's there. I highly recommend fitting a decent poly box bush tho. the stock ones are pretty shitful and you'll find your shifter bouncing around everywhere like i did before i put mine in lol.

[Cubes]

I'm not 100% sure as I haven't measured it all up yet.

Waiting on a clutch from Kudos Motorsport. Exedy GTR pressure plate & 3puk. Best price around for Exedy clutches.

I have been 'told' that you don't have to shorten the tail shaft.

When sliding my yoke in to the 25t box there's still quite a bit of room left for the tail shaft to move inwards. Thats going by the seal marks on the yoke and the alignment with the dust shield; I'm assuming it doesn't 'have' to be done when using a 2 piece as there's little if any in/out movement.

None the less I would like it to look all tidy underneath and have the yoke section lining up with the dust shield so I will most likely shorten it to what ever.

Its probably easier to snip 20mm off or so and start welding on a fresh piece of metal than attempt to weld over crap.

Mine was a factory manual, I doubt it will simply bolt up but I think it will get very very close.

With a new stock gearbox mount mine also moves around quite a bit so that will definitely be on the cards.

I think the problem comes from with my engine mounts; standard Nissan mounts appear quite soft; I've already broke one (torque side) ~1,5years after I fitted it.

I'll get the box in and look at it later; I need to let my pocket recuperate a little first.

[dangerous_daveo]

Mine had to be shortened. We ended up going with a single piece shaft in the end tho.

[1400r]

mined didnt fitted it up today R32 2 door

although the trans mounts gonna need some work

[Cubes]

Measured mine up today as the box is in, tail shaft is off to be cut rewelded and balanced.

The difference appears to be only 10mm.

1400r, hows the yoke sit inside the gearbox? Does the dust shield section just after the yoke line up with the gearbox's dust shield or does it sit in about 10mm?

The gearbox mount is a pain in the arse. With it bolted up I can only get one bolt either side in.

I'm going to drill a new hole in the gearbox so the rubber mount bolts up slightly closer to the middle of the box.

Doing this has the centre hole in the cross member line up perfectly with the rear nut hole on the floor pan.

I've got another gearbox xmember so I'm considering the cop of that and weld on to the end of my existing cross member so that I can get the 2 front bolts in. OR as the crossmember has to be spaced down a little I will grab a piece of of plate thats of the correct thickness drill 3 holes in to it and simply bolt the crossmember to that and the body. If that makes sense.

What have you others done with its height? How much higher is it really?

I didn't take the height measurement before I took the 20t box out :S

[Cubes]

Found out why you don't need to bother about shortening the tail shaft.

Speaking to Adelaide Tailshaft they said when you remove the old yoke and weld on the new you loose ~10mm off the length of the shaft anyway which is perfect as I measured mine had to be shortened 10mm.

I was told to measure from the rear gearbox seal to the centre bearing.

Also... He said they can replace the centre bearings for around $90 as they know of a suitable aftermarket item.

Another interesting bit of information. If doing lots of burnouts with sticky tyres i.e at the drags the std tail shaft spins due to the diff end being rubber mounted.

The best option is to go a single piece of which uses solid BA universal joints; he strongly recommended against replacing the std universals with aftermarkets as the only ones that fit have grease nipples so they are not solid items. Which reduces strength.

If a drag strip here in SA ever opens up I'll have a nice single piece made up; he said they don't have any issues with balancing etc.

There IS another mob here in SA that has huge issues trying to get single piece tailshafts 'right'. This wasn't mentioned by adelaide tailshaft services but other people + a couple of work shops.

So in Adelaide; Adelaide tailshaft services are the only mob to go to; as recommended by a few workshops that are in the know.

[huddy]

just keep in mind if going to track at lala etc, they'll probably check if tailshaft loop is there, so if 1 piece, maybe just keep that middle bit there...

[SirRacer]

For information sake

A r33gtst box bolts into an a31 with auto box crossmember with no issues at all. Straight into the stock slots

[grem]

For information sake

A r33gtst box bolts into an a31 with auto box crossmember with no issues at all. Straight into the stock slots

thread revival. can anyone confirm this?

just sold my other car so got some cash to spend on a spare gearbox for the cefiro.

[SirRacer]

Dude, it bloody worked with no issues at all. There is confirmation on d1nz.com on the forums there if you really dont believe me.

[NICKCEFFY]

Hey guys,

so i've just completed setting up a navara pinion assembly for the speedo drive into a r32, ceff, laurel etc, so hopefully this should help everyone out that doesn't a working speedo in their car after slipping the rb25 box into, i haven't had a chance to test whether it works completly in the car as its all apart but for intent and purpose i can't see why it wouldn't work.

So to complete the set up you will need

the standard electronic rb25 box speedo drive

Navara pinion Assembly, part number 32702 - 02G17( i'll double check the number)

small hammer

pin punch

chisel

hacksaw

drill bits

and if you have access to a lathe this makes the job a little easier

So to start with you need to get both pinions and remove the small locking type pin from half way up the shaft and set aside for re-use

on the rb25 drive remove the circlip from the base of the shaft and remove the red gear, this is what you need to fit to the Navara shaft.

Now onto the Navara assembly,

once you have removed the locking pin from up the shaft, as circled in first pic, remove the complete inner shaft out of the body and set it up in a vice, this is where you have to cut the black gear of the shaft as its moulded onto the shaft in production, i just used a hacksaw and cut it up around the body and used a hammer and chisel to break it off.

Next is having to fit the red gear onto the Navara shaft,

This is where having a lathe comes in handy as you would notice in the pic the rb25 gear has a shoulder it locks into whereas the navara shaft has a set of splines on its body, you mount the gear in to the metal lathe just using the shoulder don't use the jaws of the chuck around the actual teeth of the gear. and using a drill bit slightly bigger than the hole in the gear but smaller than the splines on the navara shaft drill it out, the lathe is set correctly will line bore the gear and keep everything inline and true once its all back together,

Once you have drilled the centre of the gear out it should tap gently into place on the shaft. The gear should sit all the way over the shaft lining the bottom of the shaft up with the bottom of the gear.

Now this is where i put the shaft back in the lathe and span it up to check everything is still in line.

if its all good and when the shaft is back in the body and the pin will slip back in without binding the shaft up you can then use the second pin out of the original rb25 speedo drive to lock the gear onto the navara shaft so it won't spin or slide off the shaft.

Now you have the pin holding the gear onto shaft re-grease the shaft back up slip it into the body of the speedo drive hammer the locking pin back in place and your done!

Go Wash up and have numerous beers!! and don't laugh at my paint skills!!

Cheers Nick

[Ceffy_SA]

Hey mate, good write up, i will be going RB25 box soon in my ceffy

[grem]

also whats the easiest way to do this without a hoist? pull it all out through the engine bay?

[1400r]

forgot the most important part which stops the bush flogging out ?

locator pin/catch (10mm bolt thingo) gotta cut a new grove into the drives body in the correct postion

so the shaft aligns correctly inside the gearbox or the cog just gets chewed out

but nice try also I used a dremel to remove the black cog and bore out the red cog then

slammed it on nice tight fit and still going 18 months later

much easier than removing the shaft etc

Edited February 27, 2009 by 1400r

[SirRacer]

also whats the easiest way to do this without a hoist? pull it all out through the engine bay?

jack it up really high!

[NICKCEFFY]

forgot the most important part which stops the bush flogging out ?

locator pin/catch (10mm bolt thingo) gotta cut a new grove into the drives body in the correct postion

so the shaft aligns correctly inside the gearbox or the cog just gets chewed out

but nice try also I used a dremel to remove the black cog and bore out the red cog then

slammed it on nice tight fit and still going 18 months later

much easier than removing the shaft etc

yeh i got that about floggin the cog out after i tried it the first time

the shaft i realised after i pulled it all apart the first time but it made it easier to take a couple of pics!

[eXquiSit]

quick question

would the write up NICKCEFFY did be the same if a rb25 box was to go into a s13?

being s13 and ceffy is similar... and r32 again is similar

any help would be great!

=)

[toffy]

does the speedo drive have the same input to the gearbox as r32? , if so then yep its the same

[eXquiSit]

from memory r32 rb20 box and s13 box are similar but my memory is fuzzy.... so can someone please confirm?