pathfinder transmission swap

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jdmser
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pathfinder transmission swap

Postby jdmser » Sat May 09, 2009 3:39 pm

Almost finished with swapping a rb25 bell housing on to a 94' pathfinder transmission. It ended up being about half the price of a rb25 transmission with the benefit of being able to source all the parts for it in the US. All of the wiring harness connector match the s14 transmission harness as well. The only down sides are the same ones you face with the rb25, shifter and mount location.















Yellow4g63
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Re: pathfinder transmission swap (jdmser)

Postby Yellow4g63 » Sat May 09, 2009 5:54 pm

The gears the same? awesome info too.

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USMCgetsome
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Re: pathfinder transmission swap (Yellow4g63)

Postby USMCgetsome » Sat May 09, 2009 6:32 pm

if this works! Man you get the award hook up of the year.

jdmser
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Postby jdmser » Sat May 09, 2009 6:37 pm

1st 2nd 3rd 4th 5th

rb20 3.321 1.902 1.308 1.000 0.759

300zx 3.214 1.925 1.302 1.000 0.752

pathfinder 3.842 2.077 1.360 1.000 0.811
Modified by jdmser at 5:43 AM 5/10/2009

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Re: (jdmser)

Postby Kansei240sx » Sat May 09, 2009 6:41 pm

Of course it works!

Its the FS5R30A transmission which is internally built the same as the Z31 87 of april plus to 89 300zx, and the Z32 transmission N/A or TT are the same.

The only differences are the bell housing.

The FS5R30A bell housing mates to the RB25/26 bell housing without modifications and depending on the vehicle you choose certain FS5R30A's have different gear ratios as listed above!

Also, quote from a different reference site. "The 87-89 z31 manual turbos are internally, the same as the nissan transmission found in z32 turbos, trucks, pathfinders, etc (FS5R30A)."

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Re: (Kansei240sx)

Postby jdmser » Sat May 09, 2009 6:48 pm

Exactly, the cool part is that the 2wd v6 pathfinder were produced from 1986-2002 so there are abundant used transmission out there for anyone who has a rb25 or 26 bell housing.

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Re: (jdmser)

Postby Yellow4g63 » Sun May 10, 2009 4:58 am

jdmser wrote:Exactly, the cool part is that the 2wd v6 pathfinder were produced from 1986-2002 so there are abundant used transmission out there for anyone who has a rb25 or 26 bell housing.
Should be interesting. 1-3 loos alot closer.

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Re: (jdmser)

Postby disrupt » Sun May 10, 2009 10:55 am

jdmser wrote:Exactly, the cool part is that the 2wd v6 pathfinder were produced from 1986-2002 so there are abundant used transmission out there for anyone who has a rb25 or 26 bell housing.
so the flange is the same on the rb25 and rb26 bell housing where it mates with the transmission casing.

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Re: (disrupt)

Postby jdmser » Sun May 10, 2009 12:48 pm

rb25 and rb26 use the same bell housing

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Carl H
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Postby Carl H » Sun May 10, 2009 5:40 pm

i like the pathy's gear ratios...should make for a quick shifting car.coupled with a 4.36 final and it should have some wicked acceleration.

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S14-NEO
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Re: (Carl H)

Postby S14-NEO » Mon May 11, 2009 11:17 am

Carl you remember you and I talking about this a while back...

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GTRs13
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Re: (S14-NEO)

Postby GTRs13 » Tue May 12, 2009 4:37 am

Hmmm. RB Pathfinder...

You can do a 2jz in a 4Runner, so I guess this will be the next big thing!

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Postby WhatsADSM » Tue May 12, 2009 5:01 am

Good info.. Always nice to have another option! Once you are done take a quick pic of the shifter mounting. Also is the tail the same total length as an RB trans, or will you need a new driveshaft?

My only other comment is that, I'm actually not a fan of the gearing at all. IMO WAY to short in first gear. There is a reason most big horsepower stuff has a long first gear.

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Re: (WhatsADSM)

Postby 240z4u » Tue May 12, 2009 5:46 am

WhatsADSM wrote:Good info.. Always nice to have another option! Once you are done take a quick pic of the shifter mounting. Also is the tail the same total length as an RB trans, or will you need a new driveshaft?

My only other comment is that, I'm actually not a fan of the gearing at all. IMO WAY to short in first gear. There is a reason most big horsepower stuff has a long first gear.
But I wanna peel out! lol

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Re: (GTRs13)

Postby Coolwhip » Tue May 12, 2009 6:35 am

GTRs13 wrote:Hmmm. RB Pathfinder...

You can do a 2jz in a 4Runner, so I guess this will be the next big thing!
I have a guy considering doing a RB Frontier. We'll see

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Re: (Coolwhip)

Postby Darius » Tue May 12, 2009 8:21 am

Would it be possible to switch out the 1st and 2nd gears from the 300ZX transmission to the pathfinder transmission?

1st and 2nd gear are already worthless on the RB25 with street tires.

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Re: (WhatsADSM)

Postby jdmser » Tue May 12, 2009 8:58 am

WhatsADSM wrote:Good info.. Always nice to have another option! Once you are done take a quick pic of the shifter mounting. Also is the tail the same total length as an RB trans, or will you need a new driveshaft?

My only other comment is that, I'm actually not a fan of the gearing at all. IMO WAY to short in first gear. There is a reason most big horsepower stuff has a long first gear.
I don't have a rb25 transmission to compare the two so I can't answer that. Once the transmission is in I'll be able to take measurement to see what kind of drive shaft will work. As for the gearing, it's for my rb24. I'm basically compensating for a lack of torque with gears. I when I get to a point where I have torque in goes the q45 diff.

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S14-NEO
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Re: (GTRs13)

Postby S14-NEO » Tue May 12, 2009 11:55 am

GTRs13 wrote:Hmmm. RB Pathfinder...

You can do a 2jz in a 4Runner, so I guess this will be the next big thing!
check out the nissan Patrol...nearly the same thing as a pathfinder and yes they Rock RB's in them overseas...

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S14-NEO
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Re: (Darius)

Postby S14-NEO » Tue May 12, 2009 11:58 am

Darius wrote:Would it be possible to switch out the 1st and 2nd gears from the 300ZX transmission to the pathfinder transmission?

1st and 2nd gear are already worthless on the RB25 with street tires.
yes providing you have the required tools to disassemble it properly and reassemble properly same size shafts and all..you will also have to change out the counter gear too id imagine cause that should also be different

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Re: (S14-NEO)

Postby Coolwhip » Wed May 13, 2009 2:43 am

S14-NEO wrote:check out the nissan Patrol...nearly the same thing as a pathfinder and yes they Rock RB's in them overseas...
Don't they rock some 4L straight 6 goodness as well

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Shocker
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Re: (Coolwhip)

Postby Shocker » Wed May 13, 2009 3:28 am

I feel like this tranny would go great with a Q45 rear end. I'm gonna run some calcs to see the gear top speeds. I'd imagine they would be about the same as stock 25 trans with a 4.10 rear.

EDIT: What is the difference in shifter locations?

Double EDIT: Just ran some quick calcs on this trans and honestly the 1st to 2nd gear shift SUCKS. Reving to 8k in 1st drops you down to around 43-4500 rpm in 2nd. Thats horrible if your running a larger turbo especially for guys 35r's and larger like me. Which would immediately make you fall out of boost.

I feel even stock turbo guys would feel this upset on shifting, the engine would slow and have to catch up once again. Checking over my stock dyno sheet of 277whp, at 4500 the car was only making around 190 hp. This shift ideally should place the rpms in the 5k+ range. The rest of the gear changes seem fine regardless of the rear end's between the Q45 and the 4.36 final.

Only way to fix this 1st 2nd gear issue is rev to 9k which really only gets to to around 5 grand on the shift, or find a way to swap out gears..

Don't get me wrong this is a great swap for someone not looking to spend much cash on a trans, however if your looking for your shifts to fall back around peak torque I'm not sure if this would be for you.
Modified by Shocker at 2:49 PM 5/13/2009

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Re: pathfinder transmission swap (jdmser)

Postby eh? » Wed May 13, 2009 3:45 am

Nice find!That tranny plus xterra 4.6 gears = traction

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Re: pathfinder transmission swap (eh?)

Postby Darius » Wed May 13, 2009 4:49 pm

Exactly why I say swap the first two gears out of the 300ZX transmission.

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Re: pathfinder transmission swap

Postby RRRRB » Sun Jul 22, 2012 9:19 am

that first gear ratio is for the auto,

anymore progress or impressions on this swap...

Also looks like the newer pathfinder frointer and xterra have the updated synchro bits

http://www.vibratesoftware.com/html_hel ... 7-2008.htm
Last edited by RRRRB on Sun Sep 09, 2012 3:52 pm, edited 1 time in total.

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Carl H
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Re: pathfinder transmission swap

Postby Carl H » Mon Jul 23, 2012 6:27 pm

after dealing with a grinding 20 trans and installing a whining 20 trans this may be a good option...however it will kinda suck with my 4.36 final.
might have to drop back to oem 4.08.

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Re: pathfinder transmission swap

Postby RRRRB » Mon Jul 23, 2012 8:49 pm

actually after further inspection i broke the pinion in the diff..

putting a 4.63 in it now

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Carl H
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Re: pathfinder transmission swap

Postby Carl H » Tue Jul 24, 2012 5:51 am

impressive, havent seen that done in a while.

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Re: pathfinder transmission swap

Postby RRRRB » Tue Jul 24, 2012 7:26 pm

yeah glad its the rear end, i had just rebuilt that tranny when i updated the turbo setup... those trannies are not fun to rebuild..

and 4.63's should make the car alot more fun... 4.08 and the rb25 tranny = retarded top speed

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Re: pathfinder transmission swap

Postby Towncivilian » Tue Jul 24, 2012 7:33 pm

If you guys use a 1986.5 - 1995 FS5R30A transmission from a 4WD Pathfinder or Hardbody (D21), you need to overfill the transmission. Please see NTB97-009a - FS5R30A TRANSMISSION WHINE. You can overfill through the shifter hole.


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