Transmission Swaps and differentials.....

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Footie570
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Transmission Swaps and differentials.....

Post by Footie570 »

So. My baja's body is officially dead. My dad is letting me use is mazda millenia to get me through the semester here in plattsburgh... ugh. Anyway, I'm searching for good subaru bodies to put my engine and transmission into. I would love to put them into a legacy. I found a nice one for a steal.... has a bad engine. Unfortunately, it has an automatic transmission, so ill have to swap my transmission as well. My question is: will my transmission bolt into this body? I know next to nothing about differentials and driveline things and havent had much luck searching about it.

In summary:
I have: 2003 Baja 2.5L Naturally Aspirated 5 Speed Manual Transmission.
I want to put my engine and transmission into: 2002 Legacy LE 2.5 Naturally aspirated with automatic transmission.

I know I will need to replace the transmission cross member, shift linkage, clutch reservoir, etc. just need to know about driveline, axles, differentials, etc.

Thanks in advance!

-A broke, desperate, college kid.
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Guacamole
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Re: Transmission Swaps and differentials.....

Post by Guacamole »

According to this (http://www.subaruforester.org/vbulletin ... ion-41059/), the front Diff & the rear diff ratios must match.

http://www.gearhack.com/myink/ViewPage. ... on%20Chart
^ This chart says all NA Bajas have a 4.11 gear ratio. Doesn't look like a 2002 Legacy auto is on this chart, and I can't find jack on the ratio for an auto trans.

Feel sorry for you man, wish there was more I could do for your predicament. :(
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anarchy1024
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Re: Transmission Swaps and differentials.....

Post by anarchy1024 »

I want to say that I thought I saw the ratio for autos was 4.44... but that could have been from a hazy dream in a different life.

If anything, manually rotate the rear differential and count the number of turns. If the shaft end of the differential turns just over 22 times for 5 turns of the wheels, it's 4.44; just over 20.5 times, it's 4.11, exactly 19.5 times, it's 3.90. A bit of work, but if you're unsure about the car's history and there's a possibility the diff+trans was replaced, you might need to do it anyway.

I have a 2002 Outback 2.5 NA Manual 5sp and 2003 Baja 2.5 NA Manual 5sp... If you can't find any info, I could measure the two shafts and see if they're the same length. I think the shaft length of the autos is different from the manuals, though.
w.rohr
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Re: Transmission Swaps and differentials.....

Post by w.rohr »

I would ask on nasioc.com because that is a much wider community and this is more of a general Subaru question.
Footie570
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Re: Transmission Swaps and differentials.....

Post by Footie570 »

I kinda took a leap of faith here and I bought the 2002 legacy, which turned out to actually be an 03. Guy had the year wrong. Drove at about 3k rpms at 60mph... Same as the baja. So I assumed the diffs. We're the same. I assumed correct! I've now done the swap and it runs and drives pretty well! Just have to figure out some of the weird wiring issues that come with a manual conversion, like the speedo.
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