Rebuilding a Transmission

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whiterabbit06

Why oh why didn't I take the blue pill?
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How-To: Rebuilding a Transmission

I figured since I was going to be doing it anyway and I haven't really been able to find anything about rebuilding a tranny I figured I would write a How-to on tranny rebuilding.

Here it goes:

You don't have to, but I found it easier to remove the clutch fork. Start by taking out this bolt.

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Pull out the Clutch Lever.

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When you start to pull out the Clutch Lever the Throw-out bearing and the fork assembly comes off.

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You can replace this seal if it is bad.

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Now we are going to tear into the transmission. Start by removing the Reverse Idler Gear Shaft bolt.

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Remove the Spedometer Gear.

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Next remove all of the case bolts and the two plugs pictured below.

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Pry the metal tab up in the picture below.

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Using Snap-Ring Plyers spread the Snap-Ring Pictured. The Intermediate Shaft should drop a bit if not start to separate the two halves of the case while spreading the ring.

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When you get the case separated it should look like this.

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Slide the pin pictured to start taking the shift linkage out.

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Remove the shift linkage bolts to remove the rest of the shift linkage.

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Remove these bolts to remove the Detent Ball/Spring and Shift Lever.

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Remove these bolts to remove the Reverse Shifting Fork.

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Remove this pin to remove the Reverse Idler Gear.

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Slide this pin out to remove the 1st/2nd/Reverse Shift Fork.

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Lift up on this tab to remove the rest of the shift forks.

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The Intermediate Shaft and the Input Shaft will slide out next and have to be taken out together.

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Next the Differential can come out and again it just slides out.

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Intermediate Shaft on the left and the Input Shaft on the right.

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If you were going to replace the Final Drive gear or if you are installing a new Differential you would remove these bolts to take off the Final Drive Gear. You would also need a press for the bearings and the Speedometer Ring Gear.

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I'm going to start with the Input Shaft first.

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Remove the bearing at the end.

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Next Remove the 5th Gear Syncro Hub.

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I found it easier to mark these when I took them out because they only line up one way.

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Next take off the Input shaft 5th Gear and Syncro.

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Between the Input Shaft 5th and 4th gears there are two bearings and a sleeve to separate the two.

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Next comes the Input Shaft 4th gear and Syncro.

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Finally the 3rd/4th gear Syncro Hub and the Inputshaft 3rd Gear, Synchro and bearing.

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You are now left with a bare Input Shaft.

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Make sure when you reassemble your transmission that the tabs on the Synchros fits into the grooves of the Synchro Hub as pictured.

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Next is the Intermediate Shaft. First you will need to take a Flat Tip Screw Driver and bend out the indent in the nut at the end of the shaft. Then take the nut off.

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Next take off the bearing.

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Next comes 5th gear.

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Followed by 4th gear.

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After 4th is 3rd.

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Now 2nd along with its Syncro bearing and sleeve.

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Next is the 1st/2nd Syncro Hub/Reverse Gear.

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Lastly is 1st gear and its Syncro.

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If you notice the bearing for 1st gear is a split bearing. When reassembling, the two halves are put on the shaft and then 1st is slid over the bearing halves.

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We are now left with a bare Intemediate Shaft.

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Now for the speedometer assembly. Take out the two bolts on the bottom.

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Next pull out the inner pump gear.

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Take out the little pin on the Speedometer shaft.

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Next pull out the outer pump gear.

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Next comes this sleeve.

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Pull out the Speedometer shaft.

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Finally we are done!

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I hope this will help anyone looking to rebuild their transmissions to replace Gears, Syncros, Diferentials or whatever other reason.

Lastly this is not from a factory manual. I do not have clearance specs so don't ask. Also by using this you understand that you do so at your own risk and I am not responsible for any dammage to your transmission.
 
Last edited:
That's not daunting anymore at all! Great write up!!! Deffinatly sticky material.
 
Thanks. It took longer to put this write up together than it did to tear down and rebuild the transmission. I also found out that the forums have a limit of 50 images to include smiles and hot-linked items. I had 55 images but I saw I could loose the five I needed.
 
Nice write up! Somebody should sticky this and/or put it in the reference section...
 
very nice write up. I would like to add that if the transmission worked fine before disassembly (ie you are adding lsd or something) then it's fine to put back together as is. If there are problems you are trying to fix it will require specialised tools, a lot of time and attention to detail. All bearings will have to be checked as well as shims, the amout of freeplay in the gears, ect. Rebuilding a beat up tranny is not for the novice or faint of heart..
 
very nice write up. I would like to add that if the transmission worked fine before disassembly (ie you are adding lsd or something) then it's fine to put back together as is. If there are problems you are trying to fix it will require specialised tools, a lot of time and attention to detail. All bearings will have to be checked as well as shims, the amout of freeplay in the gears, ect. Rebuilding a beat up tranny is not for the novice or faint of heart..

Exactly, this write-up was intended to show how everything is assembled/disassembled.
 
My buddy just asked me how hard it would be to put an LSD in his newly rebuilt S20 trans. Yay for this write up, I just refered him here.
 
Impressive, thank you for the how-to, hopefully ill never have-to-do lol. Transmissions are a little out of my league, im still stuck with the head.

None the less, awesome job.
 
Oh dude, that's an AWESOME write-up! I'm printing it and showing it to my mechanic. He usually doesn't do transmissions but with such a GREAT guideline, I'm thinking he would be inclined take the task on. I know I would. REP! Thanks again! :D
 
Was there a little NES action in the background we should know about? Perhaps a little Duck Hunt or Mario Bros. being played in between gear changes? :D

LOL, Yea I love me some Mario and my wife plays Duck Hunt.
 
LOL, Yea I love me some Mario and my wife plays Duck Hunt.
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haha! That's sweet. The classics are the best.

Let me ask you, following what you know and did and knowing that as stated before there are times when you need special tools if actually rebuilding the tranny, would you have enough confidence in yourself replacing the synchro's on your own?

The reason I ask is that I have an EX tranny with a bad 3rd and possibly 2nd gear synchro and was considering taking this write up to my mechanic and seeing if he and I couldn't figure out how to fix it. Perhaps even toss a little LSD action in there for shits and giggles. :ph34r: How would you rate the level of difficulty to replace the synchro's and possibly bearings as well?
 
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haha! That's sweet. The classics are the best.

Let me ask you, following what you know and did and knowing that as stated before there are times when you need special tools if actually rebuilding the tranny, would you have enough confidence in yourself replacing the synchro's on your own?

The reason I ask is that I have an EX tranny with a bad 3rd and possibly 2nd gear synchro and was considering taking this write up to my mechanic and seeing if he and I couldn't figure out how to fix it. Perhaps even toss a little LSD action in there for shits and giggles. :ph34r: How would you rate the level of difficulty to replace the synchro's and possibly bearings as well?

The Synchros just slide off the gears and back on they are easy to replace. The bearings you will need to pry/use an internal puller to get them out and a press to get them back in. With adding an LSD you will probably need to shim it for the case.
 
Man, I can't tell you how much I appreciate this write up. I just printed it out to add to my "Honda" book, where I have all sorts of neat pieces of information.

I'm ETERNALLY grateful! Thanks for the synchro info as well. I'll have to figure out what an "internal pull" as well as a "press" are. I'm thinking my mechanic may have an idea of what those tools are, though transmissions aren't his forte.

If I'm sucessful at this, I'm so buying you a beer. :D If you drink that is. If not, DIET PEPSI FOR THE WIN! SWOOSH!
 
Man, I can't tell you how much I appreciate this write up. I just printed it out to add to my "Honda" book, where I have all sorts of neat pieces of information.

I'm ETERNALLY grateful! Thanks for the synchro info as well. I'll have to figure out what an "internal pull" as well as a "press" are. I'm thinking my mechanic may have an idea of what those tools are, though transmissions aren't his forte.

If I'm sucessful at this, I'm so buying you a beer. :D If you drink that is. If not, DIET PEPSI FOR THE WIN! SWOOSH!

You are very welcome, and I'll take the beer over the Pepsi thank you. :)
 
You are very welcome, and I'll take the beer over the Pepsi thank you. :)

haha...that works for me. Keg for the win. SWOOSH!

What kind of beer do you drink/prefer? Or are you the kind of guy who doesn't care as long as it's cold? haha

Also, what part of Florida are you in? I'm not sure if I asked you that before.
 
haha...that works for me. Keg for the win. SWOOSH!

What kind of beer do you drink/prefer? Or are you the kind of guy who doesn't care as long as it's cold? haha

Also, what part of Florida are you in? I'm not sure if I asked you that before.

I usually drink Bud Light, but I'm not picky. That Miller Chill is addictive though. I'm in Jax.
 
I usually drink Bud Light, but I'm not picky. That Miller Chill is addictive though. I'm in Jax.


I can definitely do Bud Light or even better, Bud Select. :D I've heard that Chill is pretty good, though I rarely drink to know how good it is. haha Perhaps I'll have to take a trip to Jax to deliver the keg. :D
 
I can definitely do Bud Light or even better, Bud Select. :D I've heard that Chill is pretty good, though I rarely drink to know how good it is. haha Perhaps I'll have to take a trip to Jax to deliver the keg. :D

Sure thing let me know. :thumbsup: :beer:
 
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