ENR34 - Leaking Transfer Case

[AdiR34]

Hey y'all! So I am the owner of a shiny new '99 ENR34 25GT-Four, 5spd manual. Took it to the tire shop to get new shoes. They mismatched the front and rear axles (225/40s on rear, 225/45s on front), so AWD system went bonkers for the next day. Took it back in, they fixed it, but I noticed about 8-9 big drops of red fluid in my parking spot. Leaking has stopped, but it's clear that the transfer case may have been stressed/hurt by this debacle.

I'm taking it in for inspection tomorrow. If things are FUBAR, I have a few questions.

- ENR34 manual transmission transfer cases seem impossible to source. Can a GTR transfer case fit? Or if not the whole thing, just seals or components? GTR is 6spd, mine's 5spd, so I'm thinking no, but lmk.

- Finding a few RB25DE NEO AWD auto transmissions for sale, for decently cheap. If my only option is to swap to auto, what else will I need besides an auto-specific gauge cluster, and associated wiring?

- I imagine the R32/33 GTS4 transmissions/transfer cases are a no-go? They're not NEO engines, so unsure.

- RB25DET/4WD setup from the Stagea, any parts that transfer over?

I did search up for this on SAU and google, very little info covered.

 

This is my first post, so apologies for breaking any rules, please let me know, and thanks for the help.

[AdiR34]

Update - new drop of oil noticed. Leak seems to be continuing, but a slow/small one. 

[GTSBoy]

The 5 spd AWD boxes are all like-for like. They might not all be identical (covering >10 yrs of production means that many parts were updated as they went) but they are the same thing.

You're not going to be swapping to auto.

[AdiR34]

2 hours ago, GTSBoy said:

The 5 spd AWD boxes are all like-for like. They might not all be identical (covering >10 yrs of production means that many parts were updated as they went) but they are the same thing.

You're not going to be swapping to auto.

Appreciate it man, gives me hope based on my Google searches on availability of GTR parts. 

When you say I'm "not going to," is this in the vein of "who on earth would want auto," or more "it's impossible?"

Not trying to be rude, truly don't understand haha. I know, it'd be a madman move to go manny to auto, but if it IS my only option, I'd be curious on the lift.

[GTSBoy]

4 minutes ago, AdiR34 said:

"who on earth would want auto,"

The autos suck. Anyone with an auto wants to go manual.

Also, the one thing you don't really need to change is the dash. You don't really need to know (on the dash) what gear position you have selected. What you do have to change is the tailshaft, a bunch of wiring, probably gearbox crossmember, a bunch of fiddly shit like the spigot bearing in the back end of the crank, find a flex plate and a converter, etc. A whole lot of pain.

Most of those autos have been rightfully put into metal recycling bins, so they're not exactly easy to find either.

[AdiR34]

2 minutes ago, GTSBoy said:

The autos suck. Anyone with an auto wants to go manual.

Also, the one thing you don't really need to change is the dash. You don't really need to know (on the dash) what gear position you have selected. What you do have to change is the tailshaft, a bunch of wiring, probably gearbox crossmember, a bunch of fiddly shit like the spigot bearing in the back end of the crank, find a flex plate and a converter, etc. A whole lot of pain.

Most of those autos have been rightfully put into metal recycling bins, so they're not exactly easy to find either.

Wow, didn't realize it was THAT much of a PITA haha. 

Can I potentially source an auto transfer case to salvage parts from it for a rebuild of my manual case, if it's FUBAR? Is it like [part set a=manual], [part set a + part set b = auto], or are they configured/engineered completely differently?

[Duncan]

Before worrying too much about what to do....most likely the transfer case just got hot from all the work and has been pushing fluid out the breather.

Just start with a full fluid change with some nice synthetic auto trans oil (and have a good look at the oil that comes out).

The xfer cases can be rebuilt if necessary, don't worry too much about swapping unless you need it back on the road the next day.

BTW the gearbox and transfer case are separate (or at least, separate-able) so you you can keep your current trans and swap a new xfer case onto it if needed.

I should add, you probably have access to options we don't like Q50/60/70 AWD boxes too, I bet the xfer case interchanges

[joshuaho96]

15 hours ago, AdiR34 said:

Hey y'all! So I am the owner of a shiny new '99 ENR34 25GT-Four, 5spd manual. Took it to the tire shop to get new shoes. They mismatched the front and rear axles (225/40s on rear, 225/45s on front), so AWD system went bonkers for the next day. Took it back in, they fixed it, but I noticed about 8-9 big drops of red fluid in my parking spot. Leaking has stopped, but it's clear that the transfer case may have been stressed/hurt by this debacle.

I'm taking it in for inspection tomorrow. If things are FUBAR, I have a few questions.

- ENR34 manual transmission transfer cases seem impossible to source. Can a GTR transfer case fit? Or if not the whole thing, just seals or components? GTR is 6spd, mine's 5spd, so I'm thinking no, but lmk.

- Finding a few RB25DE NEO AWD auto transmissions for sale, for decently cheap. If my only option is to swap to auto, what else will I need besides an auto-specific gauge cluster, and associated wiring?

- I imagine the R32/33 GTS4 transmissions/transfer cases are a no-go? They're not NEO engines, so unsure.

- RB25DET/4WD setup from the Stagea, any parts that transfer over?

I did search up for this on SAU and google, very little info covered.

 

This is my first post, so apologies for breaking any rules, please let me know, and thanks for the help.

ENR34 manual transmission transfer cases are 33100-23U00 which is shared with all of the R32/R33 GT-Rs and GTS-4s. And the C34 Stagea. Do not bother with automatics, that is a huge effort to swap and the car will be worse for it. And an automatic transfer case does not have the right housing for the shifter which comes out the back of the transmission and goes through the transfer case.

I already posted my response on reddit but if you didn't see it there here it is:

You have almost certainly damaged the transfer case, the only question is how badly. Nobody can tell you how bad without more information. If you have a giant hole in the transfer case pissing out all the transfer case fluid then you need a new one. If it's not that bad then the only question is whether you burned up the clutches. Drain the transfer case oil and inspect for metal on the drain plug magnet. Small black filings are normal. Big chunks of metal or a ton of black fuzzies not so much. Fluid should be nice and red. Any other color isn't great. If the color is reasonably red and there's not a bunch of clutch material discoloring it or anything like that you probably got away with insubstantial excess wear not worth trying to fix.

If you have to rebuild or replace the transfer case keep in mind you have to pull the transmission to get it off.

[AdiR34]

You guys are amazingly knowledgeable and I appreciate it all so much. I’m currently at the local RB tuning shop, getting her inspected and diagnosed, for the t-case debacle and everything else. I’ll keep you guys posted!