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How to convert 05-06 trans to 02-04

17K views 18 replies 10 participants last post by  malkolm666  
#1 ·
I am modifying my 06 trans into an 02-04.

Tools required: 10mm socket, 12mm socket, 14mm socket, 17 mm wrench or socket, 8mm allen socket, 12mm socket, 14mm socket, pry bar or any pry tool, snap-ring expander, 6mm, 8mm, 10mm drill bit, tap-die set. That it for now I will add the correct tap size later.

Parts required: 05-06 trans, 02-04 diff, 02-04 speed sensor, 10mm bolt.

Machine shop is required to drill the hole for the 02-04 speed sensor. I will give the size when i take it to get done Monday.

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This is the pics of the trans with all the bolt removed. Remove all the 12mm bolts and mark the 3 bracket so you will remember where they go back(not in pictures). Remove the 14mm reverse gear bolt, the speed sensor, the 4 10mm shifter assembly bolts, 3 detent bolts, ball-bearing, springs, 8mm allen bolt on the side of the trans, 14mm allen bolt on top of the trans. Mark everthing so it will make everything easy to install when done.

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You must remove the 8mm allen bolt to get the shifter assembly out.
Remove the four 10mm bolts and pry the shifter assembly up and pull it out with it in neutral.

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Remove the 14mm bolt and pry the snap-ring apart while you break the trans case seal with the pry-bar. Pry the housing apart, remove the housing and set it aside. The seal is hard so you might have to use a seal break to get it open.

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Now this is what you should see. Remove the reverse gear and it shaft(not picture) and use both hand and grab on to the mainshaft, countershaft, shift forks and pull it up all at once and set it aside.

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This what you should see with it removed. Now hold on to the differential bearing and pull it strait up, if you get it cock sideway it will not come out, try to push it back down and pull it straight up and out.

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Here the photo of what it looks like side by side, notice that the 05-06 diff is longer and will not work. I had a 02-04 base model, 02-04 diff, and 05-06 differential side by side to show you guys what the size different.

02-04 left 02-04 base model center 05-06 right
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http://s155.photobucket.com/albums/s313/acuratech23/?action=view&current=DSC00772-1.jpg
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02-04 Left 05-06 left With ring gear already swap over to 02-04 diff.

Swap the ring gear from the 05-06 over to the 02-04 differential.

Now remove the 17 bolt that block the speed sensor hole and take the clutch case to the machine shop to get it drill outI will post more when it done.

I will post more when the machine is done with the process of enlarging the speedo hole because I don't have a drill bit that big.
 
#6 ·
Guys, I am doing that same setup at this time... Here is some critical info.

When swapping 05-06 gearset into 02-04 tranny casing
Note: 02-04 vs 05-06 needle bearing is different in size.

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When I put the tranny together it seemed to fall into place just fine.
I was not aware that the 02 - 04 needle bearing is actually slightly bigger than the 05 - 06

So right now the 06' counter shaft sitting in the 04' bearing will have some play which could be catastrophic once the gears are in motion.

Solution: Install 05-06 needle bearing.

91003-PPT-004 BEARING, NEEDLE (40X68X20) 2002 - 2004
91003-PPP-004 BEARING, NEEDLE (35X68X20) 2005 - 2006
 
#7 ·
Swap the ring gear from the 05-06 over to the 02-04 differential.

By "ring gear" I belive that you mean the differential gear. Not to be confused with the ring gear for the speedo sensor. As the 05-06 trany's don't have one.
 
#8 ·
What I am doing is not swapping a 02-04 clutch case but I am using a 05-06 clutch case and just modifying it to accept the 02-04 speed sensor. I am using an 02-04 diff because it has the speed senor ring on there and the 05-06 diff does not have that ring. The 05-06 diff won't accept the speed senro ring because it is not a machine finish to press on the 02-04 speed sensor ring. What I am saying here is I did not buy the 02-04 clutch case but using the 05-06 clutch case and just swapping the 02-04 diff over to use the 02-04 speed sensor. You must also drill the speed sensor hole on the 05 clutch case to accept the 02 speed sensor because there is a bolt that block that hole and must be drill out to about 28mm. By doing this I save the money of buying the $300 clutch case and all the necessary bearings.

I have found out that you must use a 1 1/8 drill bit or 28mm diameter drill bit that is about 3" length. I will have more picture up for viewing.
 
#9 ·
Its doable, but you really need to secure the case, you'll never drill perfectly straight. I have yet to install my modified case, but it should work. Oh and a drill bit is like 50 bucks. I got mine at www.mcmastercarr.com

Before:

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Drilled:

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You have to grind the tab to it sits flush and then drill and tap it.

Done:

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If you have any questions you can pm me. I'll try to answer them.
 
#16 ·
I dunno? Why did they change the open differential for the 05-06 RSX? :) That's pretty much the only reason I ask.
 
#19 · (Edited)
This is really good info, is it anyone more that has tried this conversion? With the 28mm drill?
(I measered the 02-04 hole to be 26.8-27.0mm).

Btw this thread should be moved to the "K-series transmission forum".