Getting ready to join the 6MT club

[dahoseman]

MY Car: 2005 Outback XT Limited with 5MT - various mods

 

Front diff in the 5MT seems to have lost a few teeth. It's still driveable, but involves scary violent clunks with any turns or if the the front tires have any variance in rotation between them. Instead of either cracking the transmission or trying to source a compatible tranny, I decided to just replace it with a stronger transmission.

 

Hopefully going in this weekend:

Transmission: JDM 2005 model year STI 6MT

Model: TY856WB4KA

-JDM 6MT (the "standard" later model male front axle variant)

-JDM MT shifter linkage - Included

-spec.b shifter rod and stay.

-JDM 6MT transmission cross member - Included

-2005 6MT OEM clutch + pressure plate + flywheel

-Reverse lockout cable – 35060AG010

-Rear R180 diff - included

-Rear R180 cradle - included

-2007 Legacy 4EAT Driveshaft

-Replacing R180 yolk with R160 yolk from my OBXT

-Reusing current OBXT front axles

-Rear axles 07-09 SpecB (P/N 28421AG03B) - I bit the bullet and ordered these

-axle seals (P/N 806732200)

-Tail shaft seal (806735210)

-MT Front half half shaft seals: - (L\H 806735290) and (R/H 806735300)

-Output Shaft Oil Seal (806735210)

 

-DCCD-Pro controller – Previously installed on the transmission in anticipation of a similar swap, before selling to me. It has already wired up, but was disconnected and some of the connections are a "yanked", so I'll re-crimp these with new ones.

 

I'm not terribly familiar with the DCCDPro wiring or install. Is there anything I should be aware of beforehand?

 

Is there anything obvious that I'm missing before I proceed?

[fahr_side]

I'm not terribly familiar with the DCCDPro wiring or install. Is there anything I should be aware of beforehand?

 

Just make sure which switches you're using and that you wire them accordingly. Spiider's instructions are very good.

[dahoseman]

Well, somehow I neglected that the clutch slave cylinder wasn't in the box of peripheral components.

 

It's surprisingly hard to make sure I have or am ordering the right parts. The part numbers bring up various different looking cylinders. I called the dealership to confirm and they actually told me that it's not made any more and that there are only "3 in the country right now" and would cost over $200 to get it for this transmission.

 

Any thoughts? None of that seems right?

[Max Capacity]

Don't the auto parts stores sell rebuilt slave cylinders. We got one for a Civic years ago.

 

Google it.

[dahoseman]

I ended up finding one. The Subary dealer around here is full of complete morons. They tried to tell me that it's an incredibly rare part and that there were "only three available slave cylinders in the country" and that it would be hundreds of dollars.

 

I ended up finding one at an Autozone down the road.

 

A few issues after the basic install:

1. The clutch feels "limp" for the first half the of the pedal distance. It's a disconcerting feeling.

 

2. DCCD mystery, which may be related to problem #3. The went to drive the car for a bit in its "Beta" setup. All of the wiring of the DCCDpro is installed and hooked up. However, it lurches horribly around turns. The C. Diff dial controller seems to function because it will decrease the lurching ....... However, if I move it much below the max level "full lockup", the car barely accelerates and there is an audible "spinning" noise underneath. If I slide the dial down to the minimum level and try to take off, I only hear spinning shafts/gears underneath and the car does not move.

 

3. I went to plug in the remaining harnesses on the top of the transmission. Unfortunately, they are not compatible. pictures attached. WTF?

 

on top of the 6MT, below the TMIC

http://i.imgur.com/IjC38bS.jpg

 

The male-plugs are my native plugs from my 2005 Outback XT. The female-plugs are on the 2005 STI 6MT. Not exactly compatible.

http://i.imgur.com/9iHZoZb.jpg

 

Any thoughts on any of these issues?

[fahr_side]

Sounds to me like the center diff is borked. With the diff unplugged it should be in 'open' condition which 65/35 rear bias or whatever on your trans. It should drive smoothly like this. The only time you should have binding is in 'lock' condition which is fixed 50/50 torque split.

 

 

Sent from a device using some software.

[dahoseman]

well, sh#t. I was thinking that might be the case, but I was hoping not.

 

The binding does only occur in full lock. I would turn it down to avoid the binding of the front wheels ..... however, if it is out of full lock, the car doesn't move very well. If the dial is at 90% lock, then it will drive "OK", but there is a definite lack of power/response when you step on the gas. If the dial is turned down much below 90%, there is a progressive increase in a "whirring" noise from the transmission underneath as the dial is turned down. If I turn the dial all the way down to the minimum, then the car will rock a little bit when I let out the clutch, but it won't go anywhere.

 

Any suggestions on where to get a new AP suretrac?

Can I replace it with a mechanical diff? I like mechanical components, if possible.

 

Additionally, my mechanic said that he could not connect up the pitch stop mount, so he left it hanging. Does it need a new or different dog-bone pitch stop? I think it's supposed to line up anyway. The engine seems to be pushed forward a slight bit because the radiator fan is slightly contacting the radiator hose.

 

Also, does anyone have a photo of the auto/manual and C.Diff switches with the wiring attached? I'm a little worried that I might have the pins hooked up incorrectly, so I want to make sure. The LED in the auto/manual control is not lighting up.

[dahoseman]

Does anyone have any advice on shops on long island? I'm stuck out here until the end of July ....... way out away from NYC at the far end near the Hamptons (but not the nice part)

 

Any tranny shops that might actually know how a Subaru 6MT works and be able to work on them?

[fahr_side]

You need to look at these two instruction sheets:

 

https://dccdpro.com/main/wp-content/downloads/OEM%20swap.pdf

 

https://dccdpro.com/main/wp-content/downloads/OEM%20swap2.pdf

 

Note however there are two versions of the GDB thumbwheels, those that were installed on the dash and those that were installed on the armrest. Just to make things fun the pinouts are different. Both versions of the thumbwheel have three pins. The controller cable has a red, brown and a green wire. If yours is not functioning correctly you can try swapping the red and green wires on the switch and see if that changes things. If they are the wrong way around the diff will not lock with the wheel in any position, so it sounds to me like you are wired correctly. You do know there is a jumper inside the controller (the blue one) which selects the kind of switches are in use, Spiider's own switches or the OEM ones? Make sure you have that set correctly.

 

I'd stick with it IIWY. Even getting a good used DCCD unit is not going to be more expensive than a mechanical diff, and when working right the DCCD system is truly a thing of beauty... one of the best mods I've done on the car so far.

 

Pitch stop should still fit regardless 5MT or 6MT installed.

[dahoseman]

Thanks for the info and advice.

 

Any thoughts on the harnesses on top of the tranny? Are they not supposed to be connected? They look fairly clean, as if they've been connected up until this point.

 

As for the DCCD controls, I still don't get a light in the auto/manual switch. Is the C Diff supposed to have a backlight also?

I connected them up using trailor hitch harnesses. I have done that many times with various other electrical connections that will be exposed to the elements. They're fairly hardy, good insulation, and easy to connect/disconnect. Easy cheesy.

 

Does this wiring look right? The extra unused pin in the C Diff switch makes me nervous.

[dahoseman]

You need to look at these two instruction sheets:

 

https://dccdpro.com/main/wp-content/downloads/OEM%20swap.pdf

 

https://dccdpro.com/main/wp-content/downloads/OEM%20swap2.pdf

 

Note however there are two versions of the GDB thumbwheels, those that were installed on the dash and those that were installed on the armrest. Just to make things fun the pinouts are different. Both versions of the thumbwheel have three pins. The controller cable has a red, brown and a green wire. If yours is not functioning correctly you can try swapping the red and green wires on the switch and see if that changes things. If they are the wrong way around the diff will not lock with the wheel in any position, so it sounds to me like you are wired correctly. You do know there is a jumper inside the controller (the blue one) which selects the kind of switches are in use, Spiider's own switches or the OEM ones? Make sure you have that set correctly.

 

I'd stick with it IIWY. Even getting a good used DCCD unit is not going to be more expensive than a mechanical diff, and when working right the DCCD system is truly a thing of beauty... one of the best mods I've done on the car so far.

 

Pitch stop should still fit regardless 5MT or 6MT installed.

 

If I do end up needing a replacement center diff, any suggestions on where to look for one?

Can the Suretrac be replaced with a different diff from other manufacturers or from other 6MT models?

[fahr_side]

What Suretrac?

 

 

Sent from a device using some software.

[dahoseman]

Sorry, the front diff is AP Suretrac. The center DCCD is what I meant to say.

[fahr_side]

Pretty sure all the TY856 DCCD units are interchangeable.

 

 

Sent from a device using some software.

[dahoseman]

Pretty sure all the TY856 DCCD units are interchangeable.

 

 

Sent from a device using some software.

 

I was curious about that. Online, they looks physically interchangeable. However, when they are listed for sale, they specificy "08-14 STI" or "04-05 STI". Is the year specification only because the front/rear bias is altered in different years?

[fahr_side]

The bias is only different because of the transfer ratio, 1:1 or 1.1:1

 

 

Sent from a device using some software.

[dahoseman]

well, I messed around with some of the sensors that were half-connected and tapped the axles in, which were not fully engaged. It seems to work pretty well at this point. The CEL went off and everything appears to be functioning. I'm pretty happy with it.

 

Three questions:

1) I believe the green, brown, and white wired harness next to the fluid filler is the vehicle speed sensor. It becomes a three-pin output in a 4-pin harness. From what I understand, this does not need to be connected on our cars and I can just tape it up. Correct?

 

2) There is a harness against the firewall above the turbo that looks like it has been connected to something but is not now. It has two wires, green and yellow with green stripe. What is this and do I need to have this plugged in somewhere?

 

3) While looking for the source of a "jingling" sound, I fixed a small dent in the driveshaft dust cover, but I noticed that the driveshaft seems to have at least an inch of "slide" at the 6MT splines before it hits the back of the transmission. That seems like quite a bit to me.

-Is that normal?

-Since the section between the 6MT and carrier bearing is mobile, I'm thinking of bolting up two pieces of metal to relocate the carrier bearing forward about an inch so it hold the driveshaft flush with the transmission. Thoughts?

 

Also, for laughs, here is a photo of my "elegant" solution to the TMIC getting in the way of the harnesses while I still use the car. PVC and hose clamps. I plugged up the BOV lines. I'm driving it gently to try to avoid much boost. It's entertaining to look at.

[dahoseman]

Bueller?

 

wires?

Drive shaft carrier bearing relocation?

[dahoseman]

Well, I'm going to leave the wire question to hang. The car seems to be working fine now after going through everything and reseating everything. The car feels way different. It's great.

 

I got tired and scared of the "jingling" sound of the driveshaft hitting the metal dust cap. It was pulled back by the rubber "float" on the support bearing in the center. The shaft was sitting just far enough on the end of the transmission output that it has a slight eccentric wobble under acceleration that allowed it to contact the dust cap and "ping" fairly loudly.

 

For the driveshaft center carrier bearing, I ended up clamping a piece of rubberized exhaust strap around the bearing to keep it from sliding back through the so easily. I used a crow bar to pull the front section of the sliding driveshaft forward so that it sat flush against the transmission. Then I put the strap around the floating bearing in front of the support, which is "sloshes" around inside of. I used hose camps to secure the strap around the the bearing. The outside of the strap is just barely larger than the bearing support so it keeps the shaft front being pulled back away from the tranny. It's rubbery and flexible, so it could still pass through if it needed to.

 

The "jingling" is now gone.

 

I'm curious why this occurred on mine. I haven't heard anyone else have this issue. Perhaps I just had a screwy carrier bearing rubber support?