After enjoying 4 track days and over 220k kms of less-than-gentle driving, the 6mt in my 2007 3.0r-b was showing signs of death. 4th gear, at least without double clutching, wasn't really a thing, and when cold 2nd and 6th weren't really possible even with double clutching. I was running Pentrite Pro Gear 75w90. My first thought was the Penrite fluid wasn't playing nicely with the 6mt (which is a common thing I found after running into issues ofc), so I swapped it out for some genuine squeezed dinosaur (Non-synthetic 75w90), which did make a big difference. The car was a lot more driveable, and it was only after the transmission fluid got really hot (ie. hard mountain driving/ track) that the 4th gear grind came back.
So, I did what any red blooded human being would do, and started looking for DCCD-equipped transmissions to swap into a liberty!
Nah not really. Initially I though I would just get mine rebuilt to factory specs. Until I got quotes back anyway. With quotes sitting around the 2-4k mark, I thought (for a few dumb moments anyway) that, a-la my DIY engine rebuild, I would attempt a transmission rebuild. This thought died quickly the first time I read through that part of the FSM.
I then looked into used transmissions, with the idea being to pay for the rebuild and then just install it myself. This is when I stumbled on the one- a 2003 DCCD equipped 6mt. It was a little out of my price range at the time, as I would require a new rear diff and front shafts, but I bookmarked the tab and kept looking. Every time I looked around though I kept going back to it. So I ordered it from an import shop in Sydney to get delivered to a depot in Melbourne. After waiting two weeks, bad news struck, and the gearbox never arrived.
But every cloud has a silver lining, and I found the perfect gearbox for my swap. With the correct ratio for the stock R160 3.54 ratio rear diff, the correct front shaft connectors for the stock 3.0r-b front axles and the shorter 5th and 6th ratios, the TY856UB1KA came from a JDM 2009 GRB WRX STi, and included a helical front LSD. As an added bonus it only had (claimed anyway) 85k kms on it. So I arranged for that to get delivered to the closest depot, and when it arrived I hooked up the trailer and picked it up!
First mistake was parking the trailer on a slope. I'm in a hilly area in the eastern suburbs, and not that skilled with reversing a heavy trailer (especially in a car with a lightened flywheel and a heavy duty clutch) up a steep hill, so parked where it was convenient. Turns out the gearbox was delivered with about 2 litres of gear oil in it, which proceeded to slowly leak out over the unsealed concrete driveway. FFS
After a lot of elbow grease I could finally inspect my purchase! The box arrived on a half-pallet, and included all the 6MT gearbox crossmembers and shifter assembly (which wasn't necessary for my swap but nice to have to sell with my old one). There was a bit of a patina on the aluminium casing and corrosion on the steel parts, but given the price I paid and the kilometres it had it was more than perfect! I assume it came from somewhere in Japan where they salt the roads.
Enough preamble!
The stock transmission wasn't that hard to remove all things considered, especially since the engine was out this time last year so there was minimal rust, stuck bolts or leaked oil. After disconnecting the battery, removing the intake plumbing and starter, everything else was done under the car. On jack stands as high as they go there was just enough room to access everything, and it took me about 2 hours to get the exhaust, drive shafts, shifter assembly and existing wiring out of the way. After looking closer at it and especially considering I was on my own, I decided to quickly fab up an adapter for my jack to allow it to safely hold onto the gearbox.
This took a bit longer than I though, and when I was done I was lucky enough to be joined by a mate to give me hand for the hard part- actually dropping the old box! The jack adapter was secured to the gearbox with some straps to try and make it as safe as possible. Another jack under the front of the engine to help get the angle right, and the bell housing bolts removed, meant the gearbox came pretty much straight off the engine with a minimum of fuss!
This whole assembly on the jack was still too tall to get out from under the car. Putting a piece of old MDF on the ground to protect it, the gearbox was (carefully) lifted off the jack and slid out from under the car. Even off the jack this was close- sliding under the front crossmember there was less than 5mm of free space! Trying to move the gearbox around while laying under the car was very challenging- its 85+kg so its definitely not worth attempting this on your own! This marked the end of day one of the DCCD swap project.
Went for a long drive on the Hume and it settled in at 9.6 with the windows closed and the AC off. Last time I went this way it was closer to 8.8 with the AC on! It's still not bad, and I'd expect to be able to get over 650kms at 110 from a full tank, but it is definitely worse than it was before.
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