I'm going to rebuild my own tranny!! I need input.

[itsme]

This should be a sticky if it catches on.

 

I have a '05 wagon and I have about 55K on my car and the tranny's center diff went. I can't blame the tranny much. I make 340whp and when I take it to the dragstrip and use e85 I'm around 380+ and it finally took it's toll after I added the ClutchMaster 300 setup and had some fun. Anyway I was torn between getting a STi/Spec. B 6spd $4000+ or a stock 5spd replacement (I found a '06 LGT 5spd with 30k for $1300 to my door) So now I have the old tranny that will be just sitting around. So I want to beef up the old tranny.

My goal is to build a stock tranny that can hold up to e85. I'm willing to spend upto around $1000 in parts to rebuild my tranny. I want a stronger center diff, front LSD and upgraded syncros and get whatever is needed. So anybody got leads or input on parts let me know. I will do a build up on the site and let everyone know how to do it. I have been building engines since I was 16 yrs old(I'm 38 now) so it's about time for me to build a tranny. I helped build a couple of automatics (th350,th400, C6, and, C4) and now it time to build a manual. So let's get this started. Who make a stronger center diff or where can I get it? The front LSD is pretty easy to find. What other weak points should I replace? Thanks for any input Bryan

[Th3Franz]

This might be helpful.

http://www.subaruforester.org/vbulletin/f89/center-diffs-how-replace-them-46979/

 

As far as aftermarket options go, I would go with PPG, Quaife, or Kaaz for a center diff. Which front LSD will you run? It seems to me we are limited to the JDM STI front LSD, unless you swap axles around.

 

Which brings me to the next point. Once you build up the diffs and gearbox, you might start breaking axles depending on how hard you launch the car.

 

Front diff (axle conversion?): http://www.quaife.co.uk/catalogue/products/qdh1y-0

 

Kaaz: http://www.kaazusa.com/lsd_subaru.html

 

PPG: http://www.ppgearbox.com.au/page.asp?parentid=3&parent2id=14&parent3id=31&productid=67

 

$1000 in parts won't get you much for a tranny rebuild. Each of those diffs listed is around $1k a pop. I don't know of any more durable direct swap synchros that work with the stock gearset.

[itsme]

I'm not going to launch that hard. I wanted to find out if I would be able to build a stronger tranny for a DD. If I can keep it under $2k with me doing the labor then that will be fine.

[ClimberDHexMods]

call Dave at Rallispec for a price quote on what you need to do this.

[sleeper8406]

So are you going to make a walkthrough as well on this? Now that I would like to see!

[BAC5.2]

I've been inside Subaru transmissions for many years now, and I'd like to think I am somewhat of an authority on it. Here is my advice:

 

A) If you don't have the special tools required to rebuild a trans, you are looking at an epic fail.

 

B) There are no upgraded synchros.

 

C) The least expensive front LSD is the Subaru unit, which retail in the $600 range (ish).

 

D) The STi 5MT center diffs are $750ish

 

E) If you DO decide to do this, and you already own the thousands of dollars of specialty tools, take your time. It is VERY easy to mess things up.

 

F) Realistically, the labor cost to pay someone who knows what they are doing is minimal compared the money you'll waste after putting the transmission together wrong. I've seen this one a thousand times. Some shops charge more if you ship them a box of parts that USED to be a transmission, rather than just a complete transmission.

 

If you are dead set on trying, then, again, TAKE YOUR TIME. This isn't something you can casually do. It's not something you can fudge together. It either works, and everything is great, or you forget a shim over 3rd gear, and the trans blows up after a mile.

[itsme]

So are you going to make a walkthrough as well on this? Now that I would like to see!

Don't I always.

[itsme]

I've been inside Subaru transmissions for many years now, and I'd like to think I am somewhat of an authority on it. Here is my advice:

 

A) If you don't have the special tools required to rebuild a trans, you are looking at an epic fail.

 

B) There are no upgraded synchros.

 

C) The least expensive front LSD is the Subaru unit, which retail in the $600 range (ish).

 

D) The STi 5MT center diffs are $750ish

 

E) If you DO decide to do this, and you already own the thousands of dollars of specialty tools, take your time. It is VERY easy to mess things up.

 

F) Realistically, the labor cost to pay someone who knows what they are doing is minimal compared the money you'll waste after putting the transmission together wrong. I've seen this one a thousand times. Some shops charge more if you ship them a box of parts that USED to be a transmission, rather than just a complete transmission.

 

If you are dead set on trying, then, again, TAKE YOUR TIME. This isn't something you can casually do. It's not something you can fudge together. It either works, and everything is great, or you forget a shim over 3rd gear, and the trans blows up after a mile.

So, you are saying this is going to be harder then building a engine? I will buy the parts(front and center diff) I need and of course get a manual. If it is too much then, I won't be foolish and mess up the tranny. Where can I get the Sti 5mt center diff from? Like I said I want input. Bryan

[BAC5.2]

Rallispec sells the STi center diffs.

 

I'd say it's harder than a motor. A motor, you can just kind of assume that everything is right, and it goes together very logically. A transmission requires a lot of intuition that only comes from experience.

 

Shoot me a PM and I'd be happy to provide some guidance.

[goneskiian]

What kind of front LSD are you getting for $600?

 

Since I just paid someone to do this stuff for me I'm interested in following your write up itsme!

 

Good luck!

[Max Capacity]

http://www.teammfactory.com/helical-lsd

 

Check them out. They have been supportive of the Honda guy's.

[goneskiian]

C) The least expensive front LSD is the Subaru unit, which retail in the $600 range (ish).

I was referring to this one.

[BAC5.2]

For some reason I thought the sti front diff was around 600.

 

I'd be wary of MFactory. The sets they initially brought over to the US, all failed. They have a new set, the Pro Gearset, but they arent nearly as strong or reliable as a PPG set.

[Bolksey85]

I think if you can do a motor, you can do a MT. An auto is a different story with the valve body, springs, check balls, plates, steels, all that crap. Pick up a good manual and have the internet at the ready and I think you can do it.

[itsme]

That is what I was thinking. I built modded chevys and fords with big cams a staggered valvetrains. Not just stock rebuilds. I just built a 400 pontiac tri-power for my 64 grand prix. I really can't see why I couldn't do a tranny. I will get a manual before I do anything.

I think if you can do a motor, you can do a MT. An auto is a different story with the valve body, springs, check balls, plates, steels, all that crap. Pick up a good manual and have the internet at the ready and I think you can do it.

[Max Capacity]

In for updates...Bryan, did you attempt this ?

 

I have a spare 5mt now, and was thinking....it's smarter to take it to my tranny guy and have him do it. I have done a few engines but never a tranny.

[Infamous1]

Waiting for Bryan to place blame on me for his laziness...