What Gearbox Do I Have

[t304vkcalais]

got this gearbox and just want to find out if its really a rb25 gearbox,

Edited May 2, 2011 by t304vkcalais

[The Dan]

yep, looks like it

[t304vkcalais]

looks like a rb25 gearbox? what about where the speedo goes in looks like the rb20 gearbox with that???

[Birds]

It be an RB25DET gearbox.

[t304vkcalais]

but all the 25 boxes i have seen have the speedo sender near the middle of the box, if so what model is this box out of been told its a series 1 rb25 box.

also what power can these take and how do you modify the speedo to work as manual cable driven?

tim

[Birds]

I think it may be out of an R34. I'm looking at an R33 RB25DET box right now and yes, they do have the speedo sensor in the middle of the box, along with different crossmember mounting points on the extension housing. Unless they changed these things from year to year on an R33?

The only other RWD boxes that use a similar box are the 300ZX and VL turbo, but they have different shifter setups to this one...they don't have the angled shifter housing.

Either way it's one of the big boys...people regularly run 300rwkw+ through these boxes without trouble...but that's all going to come down to how you drive and the clutch you mate it up to. You'll need an electric-manual adaptor for the speedo drive. These ones use f***in' magnets I think.

[zebra]

These ones use f***in' magnets I think.

How do magnets work?

But yeah looks to me like a R34 box

[Birds]

http://encyclopediadramatica.ch/Magnets

[The Dan]

I keep looking at it and the more I look the more different it looks.

It can't be Neo as it would have a pull style clutch which that one doesn't. It also has the speedo further back. I'll go take a pic and see if I can post one up of a 25 box.

The problem is that there is nothing to compare it's size to. If you had an RB20 box beside it, you would instantly know

[R31Nismoid]

Looks RB25 to me!

Pic to compare is here.

http://www.skylinesaustralia.com/forums/topic/287346-how-to-tell-if-u-have-a-rb25-or-rb20-manual-gearbox/

[t304vkcalais]

its def bigger then the rb20 box just need to know what it is so i can order the 1 peice tailshaft for it

[The Dan]

Looks RB25 to me!

Pic to compare is here.

http://www.skylinesaustralia.com/forums/topic/287346-how-to-tell-if-u-have-a-rb25-or-rb20-manual-gearbox/

Yeah it must be S1 I think. Definitely RB25 though.

And OP, it doesn't matter which RB25 box it is, they all take the same spline tailshaft yoke same as Z32 300ZX

[R31Nismoid]

Ye the ribbing around the top of the g'box bellhousing is another giveaway also.

RB20's have a lot more and it goes all the way around

[t304vkcalais]

you gyes are ausome, got told it came from a drift car over in japan, they bought it as a halfcut. so box is proberly rooted o well time to put some decent oil in it and see how long it lasts for

[Birds]

Best giveaway for an RB25 box is the angled shifter housing...no other Nissan boxes have them.

[t304vkcalais]

still one strange box thou, could it be a toyota box with the 25 bell housing?

[Birds]

Nup...Toyota have their own distinctive housings their cars. They look very different to Nissans.

[t304vkcalais]

well it bolts up to my rb25 so guess ille see how it goes

[webber]

I wasn't going to reply here as i thought the experts would have nailed this...

There are only a few options, it is definatly an fs5r30a as people suggest.

For those a little slow...

Options are narrowed with sloped shifter housing:

Z31 FS5R30A with RB Bell housing - rear speedo drive.

2wd Navara box with RB Bell Housing (Pretty uncommon, required a bit fair bit of mod too)

VL TURBO MX7 - has less ribbing that is further apart - center speedo

R33 RB25DET - is push, looks about right but speedo drive is in the center

R34 RB25DET - Pull Clutch, speedo drive center - so ruled out

Z32 is ruled out because it would require full case change & is center speedo, which would make it an RB25 box.. lol

My opinion... I would say Z31 FS5R30A with RB (RB25) bell housing.

I seen that on another forum your after a speedo drive.

and if your looking for a stubby mechanical speedo drive i would suggest it would be 32703-31Gxx just from having seen them.

FAST Says Z31 is 32703-58sxx the difference between the 2 maybe (i think) the mounting clip/point ??? OR... maybe electric??

I am in the middle of a write up for my site ATM, so without digging through all the info i have gathered i can't be certain... PM me for more info, and i can find out.. too late CBF ATM...

COLOURS MEAN:

32703-xxx21 21 teeth (PURPLE) Ratio 4.375:1

32703-xxx20 20 teeth (RED) Ratio 4.11:1

32702-xxx19 19 teeth (WHITE ) Ratio 3.90:1

32703-xxx18 18 teeth (BLUE) Ratio 3.70:1

32702-xxx17 17 teeth (BLACK ) Ratio 3.545:1

32702-xxx16 16 teeth (YELLOW) Ratio 3.364:1

The red speedo drive in the pic you had: Your Post I would suggest is from an RB25DE gearbox from an R33 to have electronic speedo drive.

[Birds]

Options are narrowed with sloped shifter housing:

Z31 FS5R30A with RB Bell housing - rear speedo drive.

2wd Navara box with RB Bell Housing (Pretty uncommon, required a bit fair bit of mod too)

VL TURBO MX7 - has less ribbing that is further apart - center speedo

R33 RB25DET - is push, looks about right but speedo drive is in the center

R34 RB25DET - Pull Clutch, speedo drive center - so ruled out

MX7 doesn't use a sloped shifter housing, it has a big flat one.

Didn't account for FS5R30A in a Z31 turbo...that could well be what this is. But that would mean that someone did an...engine out on a Z31

Either way it's a mongrel of a box.