6MT Master Swap Thread

No... no DCCD there.

SBT, glad to hear you're getting sorted, finally. I've still heard nothing out of Vanquish. My STi 6MT, however, is still rock solid.

So this pitch stop should work you think?

Imprezas are almost always a bit shorter between the back of the engine and the firewall, but regardless, an EJ to 5MT / 6MT / 5EAT pitchstopper is the same - at least on the Legacy.

Pitchstopper P/Ns

41040FE000 - 2004 STI 6MT

41040AE02A - 4th Gen Legacy 5MT/6MT/5EAT

41040AE02A9E - Alternate 4th Gen Legacy 5MT/6MT/5EAT

Knowing how heavily-built the STIs are, may be something to do with larger STI PS and bolts/holes

...Thinking I'll pull the entire drivetrain out of the 05 and just bolt this in. Should have everything I need...Am I inadvertently missing anything?

(edited quote)

You have all the big pieces. I'd inspect and do some preventative maintenance on the new drivetrain before installation:

• replace the rear diff-to-axle and trans-to-driveshaft seals
  
• inspect rear hub bearing assemblies & replace if questionable
  
• change the rear diff fluid, much easier off the car
  
• lube the parking brake cables while they are disconnected
  
• inspect the rear subframe diff mounts for worn/cracked bushings
  
• disassemble, clean and lube anything that is supposed to move but could rust (e.g. threads on adjustable control arms, camber bolts, etc.)
  
• YMMV - I found it easiest to drop the whole rear subframe then bolt-in the new parts since all of the bolts / nuts are then easy to access.
  

Enjoy! The install is not too bad since you have it as a unit.

All good points mang. I'm waiting on my impact driver to arrive before I start to decompose the rear end sub-frame pieces. I too plan to drop everything as a sub-frame from the 05 and just bolt the 08 bit to it and reinstall.

Question - for those who have dropped the sub-frame, were there any lessons-learned, take-aways from a realignment standpoint? I imagine these things are jigged-up on the assembly line to make sure everything is spot-on aligned, fore and aft, but not sure if the sub-frame R&R has the same alignment tolerances (or concerns).

Question - for those who have dropped the sub-frame, were there any lessons-learned, take-aways from a realignment standpoint? I imagine these things are jigged-up on the assembly line to make sure everything is spot-on aligned, fore and aft, but not sure if the sub-frame R&R has the same alignment tolerances (or concerns).

For my wagon the sub-frame fitment had very little slop or misalignment tolerance - it only fit one way. When installing it took an incremental approach to get all the mounts aligned:

• lift the subframe to just touching the chassis
  
• Thread any mounting bolts possible
  
• Manually shift the subframe to align the other bolts OR
  
  • tighten / loosen the threaded bolts to align the unthreaded mounts
    

  [*]repeat until all bolts are threaded

  [*]then tighten and final torque

If the bolts were tightened first thing there was always some mount that didn't align. My first failed attempt took 30 min, success took <10 min.

Good info. Was planning to proceed right along those lines.

What did you use to "lift" the loaded subframe? I'll have access to a lift, and a high-lift hydraulic trans jack, so I'm hoping to use that as my lift mechanism for the subframe. Presume that you installed the rear trailing arms with the subframe? Any issues where the brake lines were concerned? What's the work-around there, since I can't reuse the brake lines from the donor? Where the bolts are concerned, did you use any kind of "product" on them during reinstall?

Does anyone have info on the new manual 6spd tranny that is essentially (I understand) a 6th gear jammed into the 5 speed case? I found a YouTube video about it from Australia, but it wasn't detailed about ratios. Their main comment was that it was NOT the same performance tranny as the 6 speed in the STI/Legacy Spec B.

I'm asking because there is a very low mileage one from a wrecked Forester available in my area. I'm wondering if the case is a direct replacement for the current 5spd, what are the ratios, if the current aftermarket LSD's (Center and Front) will work, and if the gears are at least as strong as the current 5 spd.

Edit: on the Outback forum I found the 2010 6 speed ratios:

2010 Gear Ratios (6MT) - Manual

First Gear 3.454

Second Gear 1.947

Third Gear 1.296

Fourth Gear 0.972

Fifth Gear 0.825

Sixth Gear 0.695

Reverse Gear 3.636

Final Drive Ratio 4.444

Using the gear calculator http://www.teammfactory.com/gearcalculator.php this tranny has better racing ratios than my Legacy GT 5 spd. I spend 90 % of time in 3-4 and these work out even better for the 3-4-5 powerband while still having the top speed.

That trans was designed to handle the torque of the Subaru 2.0TD so it's pretty stout, internally, despite it still being a split-case setup.

Shift mechanism sits on top of the transmission so shifter and clearance may be an issue. Driveshaft may also be an issue - The 4.444 FDR is designed to best work with the very large Outback tires. Smaller "GT" tires would change the ratio dramatically.

Just looking at the numbers - RPM vs Speed per gear:

2.5GT 5MT

2.5GT Spec B 6MT

2250 12.7 21.4 31.0 41.4 54.5

2250 12.2 19.9 29.2 39.1 49.9 62.9

2500 14.1 23.7 34.5 46.0 60.6

2500 13.6 22.1 32.5 43.4 55.4 69.9

2750 15.5 26.1 37.9 50.6 66.6

2750 14.9 24.3 35.7 47.8 61.0 76.8

3000 16.9 28.5 41.4 55.2 72.7

3000 16.3 26.5 39.0 52.1 66.5 83.8

3250 18.3 30.9 44.8 59.8 78.7

3250 17.7 28.7 42.2 56.5 72.1 90.8

3500 19.8 33.2 48.3 64.4 84.8

3500 19.0 30.9 45.5 60.8 77.6 97.8

3750 21.2 35.6 51.7 69.0 90.8

3750 20.4 33.1 48.7 65.2 83.2 104.8

4000 22.6 38.0 55.2 73.6 96.9

4000 21.7 35.4 52.0 69.5 88.7 111.8

4250 24.0 40.4 58.6 78.2 102.9

4250 23.1 37.6 55.2 73.8 94.2 118.8

4500 25.4 42.7 62.1 82.8 109.0

4500 24.5 39.8 58.5 78.2 99.8 125.8

4750 26.8 45.1 65.5 87.3 115.0

4750 25.8 42.0 61.7 82.5 105.3 132.7

5000 28.2 47.5 69.0 91.9 121.1

5000 27.2 44.2 64.9 86.9 110.9 139.7

Miniscule in 1st, but 2nd on up, more telling. Tire sizing will likely have a greater impact on acceleration, all else equal. In real terms though, you want to get the Spec B trans into 6th as soon as practical, because you're turning more RPMs in the lower gears. Especially 2-5th.