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1986 GL-10 transmission swap

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So I have a 86' GL-10 with 355k on the body, I'm not sure of the mileage on the transmission, but it's starting to be extremely rough shifting all gears, and sometimes doesn't like to go into first unless I'm at a complete stop, how difficult is it to replace the transmission myself on the 5sp 4wd version.  I've done a trans swap on a 2001 Camaro, but that was rwd.  I guess tied to that would be asking if there is anyone in the greater seattle area that would be able to do it for me, obviously for a price.  I plan on driving the car cross country in May with some friends so I'm trying to get it into shape for that.  I've replaced everything short of the radiator(perfect condition), trans(shifts hella rough), engine(makes a ticking noise while idling, if sitting for more than 5 minutes, also burns some oil when using trans to decelerate) and diff(seals on rear diff are slightly leaky but 4wd works solidly) at this point.




Edited by Arsenal25boy
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Shouldn't be that difficult with just basic tools.  Have to remove the front CV axles that could be a challenge.  Plan on replacing the clutch/pressure plate/throwout bearing and have the flywheel machined.  Also good time to check the condition of the driveshaft U-joints. Good luck on the trip. 

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You need a punch to tap the pins out of the cv axles in the trans. Tap pins and the axle slides right off the trans.


The cvs onjy align one way when reinstalling. Look at grooves and you can get it right the first time. The two holes have to line up and they only line up one way - so they can be 180 degrees off.


Otherwise. It’s fairly straight forward for a trans swap. Nothing overly tricky - but it’s a sizable job and working under tha car or pulling the entire lump.


Separating engine and trans can take a bit. But work your way around the bell housing slowly increasing the gap with screwdriver, chisel, pry bar.


Engine will need lifted/supported up a little bit off the crossmember for clearance and angle to get the trans to slide back and out.


You can also pull the engine and trans together with an engine lift. Have plenty of ceiling it can come out high and angled.


Otherwise yeah not much to it - exhaust, CV axles, rear drive shaft, disconnect connectors, shifter linkage and speedo cable.


You can remove the trans without disconnecting the axles from the knuckles but it’s a bit wonky. With trans ready to come out - pull back slightly and slide one cv off the trans stub. Just tap the pin out (3/16” punch) Then maneuver trans such that you can pull the other axle off as well. Tricky working under the car, taming the large awkward trans but it can be some if you want to avoid pulling the CVs.

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Done just this to my GLTA years back. Bought my donor car for $250 swapped out bad thermostat and assessed whole car on road next three week s until rego ran out.


My turbo four door 4wd sedan had 3.45 diff in front 3.7 in rear. Lucky donor was 3.7 anyway.


Need flywheel to rear diff if not correct ratio in your GL10


Need manual clutch pedal or even whole pedal box


Under console should find eight? Wire connector in one row for trans wiring. Disconnect on conversion and jumper two fattest black wires to make it start bypasses D or P start switch

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I'm sad to say now my trouble is just finding the transmission, does anyone know a good place to get them from, or to get my trans rebuilt at in the greater seattle area?

There are used parts suppliers that sell used Subaru transmissions, located in every major city.  Since you are going to be loosening and lifting your engine to get the transmission back in, better drain the engine oil first so that you can remove the oil pan, clean the surfaces, caulk the crap out of the gasket, clean the bolt holes and reinstall the bolts with thread lock.  Also, the stick mechanism on top of the transmission gets worn out.  There are nylon parts there that you can replace first, before you yank the transmission, just to see whether that was the cause of your shifting problems.

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